AMC 8 L1: Calculation Tricks

Complete problem set with solutions and individual problem pages

Problem 6 Easy

Find the value of expression 100-98+96-94+92-90+\cdots +8-6+4-2. (2016 AMC 8 Problem, Question #8)

  • A.

    20

  • B.

    40

  • C.

    50

  • D.

    80

  • E.

    100

Answer:C

100-98+96-94+92-90+\cdots +8-6+4-2

=(100-98)+(96-94)+(92-90)+\cdots +(8-6)+(4-2)

=2\times25

=50