Answer:
1. 168 cm^{2}
2. 156 in^{2}
3. 30 cm^{2}
4. 360 ft^{2}
Step-by-step explanation:
All ratio questions. We can set up proportions then cross multiply
1. \frac{8}{12} \frac{112}{x}
8x = (112 x 12)
8x = 1344
x = 168m
2.\frac{4}{8} \frac{78}{x}
4x = (78 x 8)
4x = 624
x = 156in
3. \frac{5}{2} \frac{75}{x}
5x = (75 x 2)
x = 30cm
4. \frac{8}{10} \frac{288}{x}
8x = ( 288 x 10 )
8x = 2880
x =360ft
