Answer:
100 in²
Step-by-step explanation:
Since the figures are similar
the linear ratio of sides = a : b , then
ratio of areas = a² : b²
ratio of sides = 15 : 21 = 5 : 7
ratio of areas = 5² : 7² = 25 : 49
let the area of the smaller figure be x then by proportion
=
( cross- multiply )
49x = 4900 ( divide both sides by 49 )
x = 100
Area of smaller figure is 100 in²