Answer:
Part 1) Helen's age is 32 years old and Jane's age is 24 years old
Part 2) 13 twenty-dollar bills
Step-by-step explanation:
Part 1) Helen is 8 years older than Jane. Twenty years ago Helen was three times as old as Jane. How old is each now and what is the equation?
Let
x----> Helen's age
y---> Jane's age
we know that
x=y+8 ----> equation A
(x-20)=3(y-20) -----> equation B
substitute equation A in equation B and solve for y
(y+8-20)=3(y-20)
y-12=3y-60
3y-y=60-12
2y=48
y=24 years
Find the value of x
x=y+8
x=24+8=32 years
Part 2)
Let
x-----> the number of five-dollar bills
y----> the number of twenty-dollar bills
we know that
5x+20y=305 -----> equation A
y=x+4 ------> x=y-4 ------> equation B
substitute equation B in equation A and solve for y
5(y-4)+20y=305
5y-20+20y=305
25y=325
y=13 twenty-dollar bills
Find the value of x
x=y-4
x=13-4=9 five-dollar bills
Answer:
V ≈ 8.67x10^7 ft^3
Step-by-step explanation:
We know that the volume of a pyramid is V= (lwh)/3
Since it is a square pyramid, it means that the length and the width are the same:
Length=755.9 feet
Width=755.9 feet
Height=455.4 feet
So, the volume is :
V = [(755.9)(755.9)(455.4)]/3
V = 86736214.158 ft^3
V ≈ 8.67x10^7 ft^3
Hope this helps!
Mark brainliest if u think I helped! Would really appreciate!