If x : y = 3 : 4, then (7x + 2y) : (7x − 2y) is equal to?
Show answer & explanation
Correct answer: D
Explanation
x : y = 3 : 4
according to formula
x = 3k, y = 4k
(7x + 2y) : (7x − 2y)
= (7×3k + 2×4k) : (7×3k − 2×4k)
= (21k + 8k) : (21k − 8k)
= 29k : 13k
= 29 : 13