Answer:
The 5th day must be 90
Step-by-step explanation:
The first 4 days averaged out to 80
You can find their total just by multiplying by 4. That won't tell you the exact values, but it will tell you their total when you add the 4 of them together.
80*4 = 320
Now you need to add another day into the mix. Call it x
320 + x
Now there are 5 days, not 4, and the new total is 82.
(320 + x) / 5 = 82 Multiply both sides by 5
5*(320 + x) / 5 = 82 *5
320 + x = 410 Subtract 320
-320 -320
x = 90
Answer:
Box B i think.
Step-by-step explanation:
The heat produced by current I is
H = I²R
where
R = resistance.
According to the formula, heat produced is proportional to the square of the current.
When a current of I = 2 amps is applied, the heat produced is
H = 10x³ + 80.
This heat includes heat due to a fixed current of 2 amps, and heat due to a variable current of x amps.
Because the heat produced is proportional to the square of the current, write the expressions as
H = (10x)*(x²) + 20*(2²)
The second term on the right is heat due to the fixed current of 2 amps, written as
20*(2²).
Therefore the fixed resistance is R = 20 ohms, and the square of the fixed current is 2².
The first term represents heat due to variable resistance, written as
(10x)*(x²).
Therefore the variable resistance is 10x, and the square of the variable current is x².
Answer:
The variable current is 10x.
Answer:
9(4/3)
Step-by-step explanation:
you add up the hours of each of the girls so, 3(1/2)+4(1/3)+2