1/32 maybe................
Life expectancy of dollar bill = d
life expectancy of coin = c
d = 1/20 c
substitute value in for c (30)
d = 1/20 * 30
d = 30/20
d = 1.5
life expectancy of a dollar bill = 1.5 years
Answer:
140.74
Step-by-step explanation:
1.area of right triangle
1/2*b*h=1/2*20*18=180
2.area of semi circle
1/2*pi*r^2=1/2*pi*5^2=39.26
r= d/2
180-39.26=140.74