Answer:
a=50 b=20
Step-by-step explanation:
Call A and B the 2 present ages.
Ten years from now, A is twice as old as B -->
(A + 10) = 2(B + 10) (1)
Five years ago, A was 3 times as old as B -->
(A - 5) = 3(B - 5) (2).
Solve the system (1) and (2).
From (2) --> A = 3B - 15 + 5 = 3B - 10.
Replace this value of A into (1) -->
3B - 10 + 10 = 2B + 20 --> B = 20. Then,
A = 3B - 10 = 60 - 10 = 50.
Check
!0 years from now --> A = 60 and B = 30 --> A = 2B .OK
5 years ago --> A = 45 and B = 15 --> A = 3B. OK
Answer:
a) 
b) 
c) 
Step-by-step explanation:
For total cost function
, average cost is given by
i.e., total cost divided by number of units produced.
Marginal average cost function refers to derivative of the average cost function i.e., 
Given:
Average cost = 
a)
At x = 50 units,

b)
Average cost = 
c)
Marginal average cost:
Differentiate average cost with respect to 
Take 
using quotient rule, 
Therefore,

Answer:

Step-by-step explanation:
We want to find the sum of

We can rewrite this as

This becomes;

Recall that;

This implies that;

Combine like terms:

Ava took 5 minutes out of 60 in an hour to do half a mile
5×2=10
60/10=6mph
Damon took 3 minutes out of 60
3×2=6
60/6= 10mph
Reina took 4 minutes out of 60
4×2=8
60/8= 7.5mph