First you need to get the unit rate by dividing 715 by 13, getting 55 miles per hour. You then will need to divide 495 by 55 to get the answer of 9
John's hourly rate is 1/8 of the room per hour.
Rick's hourly rate is 1/2 of the room per hour.
Molli's hourly rate would be 3/8 of the room per hour.
It takes Molli 2 2/3 hours to paint the room alone.
Explanation
Since John paints the entire room (100%=1) in 8 hours, he would paint 1/8 of the room in 1 hour.
Since Rick paints the entire room (100%=1) in 2 hours, he would paint 1/2 of it in 2 hour.
We do not yet know Molli's rate, so we will call it x.
We know that 1/8+1/2+x = 1 hour.
We will use 8 as a common denominator:
1/8+4/8+8x/8 = 1
Adding the numerators,
(1+4+8x)/8 = 1
Multiply both sides by 8:
1+4+8x = 8
Add like terms:
5+8x = 8
Subtract 5 from both sides:
5+8x-5=8-5
8x=3
Divide both sides by 8:
8x/8 = 3/8
x = 3/8
Molli's rate is 3/8.
Since she can paint 3/8 of the room in 1 hour, we can set up the equation
3/8x = 1
Divide both sides by 3/8:
3/8x ÷ 3/8 = 1 ÷ 3/8
x = 1/1 ÷ 3/8 = 1/1 × 8/3 = 8/3
x = 2 2/3
This is the amount of time it takes Molli to paint the entire room.
Answer:
12
Step-by-step explanation:
it is a square and 144 is the area
√144
This gives us 12 for each side
