Given
gas prices are now $3.75 and it up 10% from 6 months ago.
Find out how much were gas prices 6 months ago.
To proof
gas prices now = $3.75
let the gas price 6 month ago = x
gas price now is rise up 10% from 6 months ago
First write 10% in simpler form

= 0.1
Now the equation becomes
0.1x + x = 3.75
1.1x = 3.75

x = 3.41 (approx)
Thus gas prices 6 months ago be $ 3.41 (approx )
Hence proved
Answer:
20 masks and 100 ventilators
Step-by-step explanation:
I assume the problem ask to maximize the profit of the company.
Let's define the following variables
v: ventilator
m: mask
Restictions:
m + v ≤ 120
10 ≤ m ≤ 50
40 ≤ v ≤ 100
Profit function:
P = 10*m + 65*v
The system of restrictions can be seen in the figure attached. The five points marked are the vertices of the feasible region (the solution is one of these points). Replacing them in the profit function:
point Profit function:
(10, 100) 10*10 + 65*100 = 6600
(20, 100) 10*20 + 65*100 = 6700
(50, 70) 10*50 + 65*70 = 5050
(50, 40) 10*50 + 65*40 = 3100
(10, 40) 10*10 + 65*40 = 2700
Then, the profit maximization is obtained when 20 masks and 100 ventilators are produced.
Multiply all three numbers to get 560 yards cubed :))
Answer:
C≈9.42m
Using any of this formulas
C=2πr
C=2πrd=2r
Solution:
C=πd=π·3≈9.42478m