Answer:
<u>The ages of Paul and Selena are 13 and 7 years old.</u>
Step-by-step explanation:
Age of Paul = x
Age of Selena = x -6
Age of Paul and Selena in 15 years:
x + 15 = 4 (x - 6)
x + 15 = 4x - 24
x - 4x = -24 - 15
- 3x = -39
x = 13
<u>Paul now is 13 years old and Selena is 7 years old. In 15 years, Paul will be 28, that is 4 times the present age of Selena.</u>
Answer:
c is the answer
Step-by-step explanation:
Answer:
Step-by-step explanation:
Given:
x = 2cost,
t = (1/2)arccosx
y = 2sint
dy/dx = dy/dt . dt/dx
dy/dt = 2cost
dt/dx = -1/√(1 - x²)
dy/dx = -2cost/√(1 - x²)
Differentiate again to obtain d²y/dx²
d²y/dx² = 2sint/√(1 - x²) - 2xcost/(1 - x²)^(-3/2)
At t = π/4, we have
(√2)/√(1 - x²) - (√2)x(1 - x²)^(3/2)
Answer: 36 years
Step-by-step explanation:
You can use the Rule of 72 to calculate how long it might take the house to double in value.
The Rule of 72 works by dividing 72 by the interest rate as a whole number and the result will be a rough estimate of the time in years it will take for the investment to double in size:
= 72 / 2
= 36 years
Answer:
572000
Step-by-step explanation:
The population reduced by 12%, so (100-12)=88% is remaining.
So, 88% of 650000= 0.88 x 650000
= 572000
