Answer:
11.25
Explanation:
Ratio of yogurt : ratio of idiot = 1 : 4
Idiot had 45
Yogurt = x
Ratio of yogurt : ratio of idiot = x : 45
Equate the ratios
1 : 4 = x : 45
1/4 = x/45
Cross product
1 * 45 = 4 * x
45 = 4x
x = 45/4
x = 11.25
Yogurt = x = 11.25