Consider four consecutive even integers represented by a, b, c, and d, where a < b < c < d. What is the difference between c + d and a + b?

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Let the integers be a, a + 2, a + 4, and a + 6. Then, we…

Comments

DaryaMay 14, 2024

Thank for sharing!!!

RajuanMay 19, 2024

thank you for sharing

AdityaJul 22

wait why isn't it just the gap between c and a? I keep second-guessing myself on these.

MadhurAug 2

because it's (c+d) minus (a+b), you're adding two numbers on each side so it doubles up. pick actual numbers and it's obvious

IshikaSep 22

thanks, helpful reminder that picking numbers like 2,4,6,8 works fine here

ManelMay 23

c + d vs a + b... I tried a=0 and got confused for a sec but then it clicked. nice little question

What this question tests

Your command of divisibility, primes, factors, parity, and how the GMAT tests properties of integers.

Forgetting that 1 is not prime, that 0 is divisible by every integer, or that negative numbers flip your assumptions.