Answer:
x = 6/7 of a puzzle
Explanation:
Number of puzzle : time taken
= 3/4 : 7/8
How much a puzzle can she complete in an hour?
Let
x = number of puzzle to complete
Number of puzzle : time taken
= x : 1
Equate both ratios to solve for x
3/4 : 7/8 = x : 1
3/4 ÷ 7/8 = x / 1
3/4 × 8/7 = x / 1
24/28 = x / 1
Cross product
24 * 1 = 28 * x
24 = 28x
x = 24/28
= 6/7
x = 6/7 of a puzzle