you don't have enough info, we need to know how old he was when he was twice her age, or how old she was
An example of the ratio 4:1 could be, in a school for every 4 girls there is 1 boy. Or something similar:)
Answer:
Step-by-step explanation:
Average Temperatures Suppose the temperature (degrees F) in a river at a point x meters downstream from a factory that is discharging hot water into the river is given by
T(x) = 160-0.05x^2
a. [0, 10]
For x = 0
T(0) = 160 - 0.05 × 0^2
T(0) = 160
For x = 10
T(10) = 160 - 0.05 × 10^2
T(10) = 160 - 5 = 155
The average temperature
= (160 + 155)/2 = 157.5
b. [10, 40]
For x = 10
T(10) = 160 - 0.05 × 10^2
T(10) = 160 - 5 = 155
For x = 40
T(10) = 160 - 0.05 × 40^2
T(10) = 160 - 80 = 80
The average temperature
= (80 + 155)/2 = 117.5
c. [0, 40]
For x = 0
T(0) = 160 - 0.05 × 0^2
T(0) = 160
For x = 40
T(10) = 160 - 0.05 × 40^2
T(10) = 160 - 80 = 80
The average temperature
= (160 + 80)/2 = 120
