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    • Showing results for:
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()
    • Close
  • Ravel Oliveira
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    .a{fill-rule:evenodd;}techdegree
    Ravel Oliveira
    Front End Web Development Techdegree Student 10,869 Points

    Why am i getting the 'Bummer: Both the `reduce` and `filter` methods have not been called yet.' ERROR?

    Posted on Oct 14, 2024 by Ravel Oliveira
    .a{fill-rule:evenodd;}techdegree
    Ravel Oliveira
    Front End Web Development Techdegree Student 10,869 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Amy Preci
    Amy Preci
    6,247 Points

    Did anyone else get an error when adding .toFixed(2)?

    Posted on Feb 2, 2023 by Amy Preci
    Amy Preci
    6,247 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Cole Smith
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    .a{fill-rule:evenodd;}techdegree
    Cole Smith
    Web Development Techdegree Student 13,802 Points

    how do I complete this callback function?

    Posted on Apr 4, 2022 by Cole Smith
    .a{fill-rule:evenodd;}techdegree
    Cole Smith
    Web Development Techdegree Student 13,802 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Keytron Brown
    Keytron Brown
    15,828 Points

    Unexpected Token '{'

    Posted on Nov 4, 2021 by Keytron Brown
    Keytron Brown
    15,828 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • ramoshe
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    .a{fill-rule:evenodd;}techdegree seal-36
    ramoshe
    Full Stack JavaScript Techdegree Graduate 25,795 Points

    Why is it telling me "Both the `reduce` and `filter` have not been called?

    Posted on Jul 1, 2021 by ramoshe
    .a{fill-rule:evenodd;}techdegree seal-36
    ramoshe
    Full Stack JavaScript Techdegree Graduate 25,795 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Kennedy Malonga
    Kennedy Malonga
    18,790 Points

    help please

    Posted on Jun 8, 2021 by Kennedy Malonga
    Kennedy Malonga
    18,790 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • Joe Mbome
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    Joe Mbome
    Front End Web Development Techdegree Graduate 17,250 Points

    Using the filter and reduce methods on the purchaseItems array, add the total price of all the groceries (items with a d

    Posted on Mar 26, 2021 by Joe Mbome
    .a{fill-rule:evenodd;}techdegree seal-36
    Joe Mbome
    Front End Web Development Techdegree Graduate 17,250 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • Ryohei Mahiko
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    Ryohei Mahiko
    Front End Web Development Techdegree Graduate 13,950 Points

    Both the `reduce` and `filter` methods have not been called yet?

    Posted on Aug 4, 2020 by Ryohei Mahiko
    .a{fill-rule:evenodd;}techdegree seal-36
    Ryohei Mahiko
    Front End Web Development Techdegree Graduate 13,950 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • Zachary Danz
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    .a{fill-rule:evenodd;}techdegree seal-36
    Zachary Danz
    Front End Web Development Techdegree Graduate 15,024 Points

    Adding the .toFixed(2) Method results in this quiz failing

    Posted on May 26, 2020 by Zachary Danz
    .a{fill-rule:evenodd;}techdegree seal-36
    Zachary Danz
    Front End Web Development Techdegree Graduate 15,024 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • Martin Coton
    Martin Coton
    3,015 Points

    My solution works, check fails it however.

    Posted on May 6, 2020 by Martin Coton
    Martin Coton
    3,015 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • MIHA W.LEE
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    .a{fill-rule:evenodd;}techdegree seal-36
    MIHA W.LEE
    PHP Development Techdegree Graduate 25,452 Points

    About reduce() and filter()

    Posted on Oct 29, 2019 by MIHA W.LEE
    .a{fill-rule:evenodd;}techdegree seal-36
    MIHA W.LEE
    PHP Development Techdegree Graduate 25,452 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Steven mudie
    Steven mudie
    5,523 Points

    bug in the learning material

    Posted on May 21, 2019 by Steven mudie
    Steven mudie
    5,523 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Ali A
    Ali A
    15,523 Points

    What's wrong?

    Posted on May 15, 2019 by Ali A
    Ali A
    15,523 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Brian Johnson
    seal-mask
    PLUS
    .a{fill-rule:evenodd;}techdegree seal-36
    Brian Johnson
    Front End Web Development Techdegree Graduate 20,818 Points

    These JavaScript problems are difficult. Can someone tell me what I'm wrong?

    Posted on Dec 31, 2018 by Brian Johnson
    .a{fill-rule:evenodd;}techdegree seal-36
    Brian Johnson
    Front End Web Development Techdegree Graduate 20,818 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • Joshua Landi
    Joshua Landi
    3,643 Points

    Says .filter and .reduce have not been called when they have.

    Posted on Dec 27, 2018 by Joshua Landi
    Joshua Landi
    3,643 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Humoyunmirzo Nosirov
    PLUS
    Humoyunmirzo Nosirov
    Courses Plus Student 5,154 Points

    please anyone , give me some help

    Posted on Aug 31, 2018 by Humoyunmirzo Nosirov
    Humoyunmirzo Nosirov
    Courses Plus Student 5,154 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Kaitlyn Dodds
    Kaitlyn Dodds
    32,545 Points

    Not sure this code challenge is working correctly.

    Posted on Apr 24, 2018 by Kaitlyn Dodds
    Kaitlyn Dodds
    32,545 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • ludopuig
    seal-mask
    .a{fill-rule:evenodd;}techdegree
    ludopuig
    Full Stack JavaScript Techdegree Student 6,436 Points

    not working

    Posted on Apr 20, 2018 by ludopuig
    .a{fill-rule:evenodd;}techdegree
    ludopuig
    Full Stack JavaScript Techdegree Student 6,436 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • Giovanni Quaglia
    Giovanni Quaglia
    1,829 Points

    I can't get why i can't pass the test. The code seems to work on JS Bin, but here it does not

    Posted on Dec 11, 2017 by Giovanni Quaglia
    Giovanni Quaglia
    1,829 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Ioana Rusu
    Ioana Rusu
    9,599 Points

    Help with this challenge

    Posted on Nov 17, 2017 by Ioana Rusu
    Ioana Rusu
    9,599 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Jonathan Grieve
    MOD
    Jonathan Grieve
    Treehouse Moderator 91,254 Points

    Problem with the reducer method for getting total of groceries

    Posted on Nov 8, 2017 by Jonathan Grieve
    Jonathan Grieve
    Treehouse Moderator 91,254 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    1 Answer

  • Doug Hawkinson
    seal-mask
    .a{fill-rule:evenodd;}techdegree
    Doug Hawkinson
    Full Stack JavaScript Techdegree Student 25,073 Points

    There is something really bizarre going on with this challenge. Fails in the challenge workspace, but on offline.

    Posted on Nov 2, 2017 by Doug Hawkinson
    .a{fill-rule:evenodd;}techdegree
    Doug Hawkinson
    Full Stack JavaScript Techdegree Student 25,073 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

  • Anik Devaughn
    Anik Devaughn
    7,751 Points

    Challenge Task 1: Using the filter and reduce methods on the purchaseItems array, add the total price of all the......

    Posted on Oct 29, 2017 by Anik Devaughn
    Anik Devaughn
    7,751 Points
    • JavaScript
    • JavaScript Array Iteration Methods
    • Combining Array Methods
    • Combining filter() and reduce()

    2 Answers

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