Answer: 6 large frames and 12 small frames
Step-by-step explanation:
We define the following:
x = number of large frames
y = number of small frames
Make the following equations:
x + y = 18
19x + 9y = 222
Use system of equations to solve. We find the value of x first.
y = 18 - x
⇒ 19x + 9(18 - x) = 222
⇒ 19x + 162 - 9x = 222
⇒ 10x + 162 = 222
⇒ 10x = 60
⇒ x = 6
Find value of y:
6 + y = 18
y = 12
∴ 6 large frames and 12 small frames were purchased.
Answer:
x = 2
Step-by-step explanation:
In general, to find the surface area of a prism (a shape with 2 bases) is
Area of Base*2 + Lateral Area (Lateral area = Perimeter of bases * height)
#9 Area of base= 2×1÷2=1 *2=2
Lateral area= 2+1+2.2=5.2 5.2*3=15.6
Answer=17.6
#10 Area of Base= 120*2=240
Lateral Area=500
Answer=740
#11
Area of base=8*2=16
Lateral Area= 41.4
Answer=57.4