Which of the following represents \(x\cdot y=64\)?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → \(32:x=y:2\)
In a proportion \(a:b=c:d\), the product of the extremes equals the product of the means: \(a\times d=b\times c\). Each option is turned into an equation this way.
Option (1) \(8:x=8:y\) gives \(8y=8x\), that is \(x=y\)
Option (2) \(x:8=y:8\) gives \(8x=8y\), that is \(x=y\)
Option (3) \(x:16=y:4\) gives \(4x=16y\), that is \(x=4y\)
Option (4) \(32:x=y:2\) gives \(32\times2=x\times y\), that is \(xy=64\)