To find the answer set up an equation:

Using this set up we can cross our units of pages since they are on opposite side of the proportion, leaving us with the desired units of hours.
Then divide 400 by 65 which will give us our answer: 6.15 or about 6 hours for Jamie to finish her reading.
9:15
9÷3:15÷3
3:5
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5x + 4 = 7x
Subtract 4 from both sides.
5x = 7x - 4
Subtract 7x from both sides.
5x - 7x = -4
Simplify.
-2x = -4
Divide both sides by -2.
x = 4/2
x = 2
~Hope I helped!~
Which problem? I will help you if you tell me what problem it is.
We can use 2x3x3. (2 x pi x radius)
This gives us 18. C=18