Found this when I was doing my own work, hope this helps.
First subtract 30-23 that’d be the value of UV(7) now subtract 18 from 7, the answer will be 11 therefore TU is 11.
The volume of the pyramid would be 80 cubic centimeters. The reason for this is because the formula for volume of a pyramid is 1/3bh, so if all the dimensions are the same for both figures, just divide the volume of the prism by three to find the volume of the pyramid. If you do this 240÷3=80 or the volume of the pyramid.
Let
y-------> number of books read during the month 
x------> number of picture of a book
we know that
in this problem
for 
calculate y
therefore
the answer is
The number of books read during the month is 
The bar should be 8 1/24 from the each edge of the door.
We need to subtract 10 1/4 from 26 1/3 to get the fraction of the space not covered by the towel bar.
We also need to divide the difference by 2 because we placed the towel bar in the center of the door.
1st we need to convert the mixed fractions into fractions to perform subtraction.
26 1/3 = ((26*3)+1)/3 = 79/3
10 1/4 = ((10*4)+1)/4 = 41/4
Steps in Subtracting Fractions
Step 1. Make sure the denominator is the same. 3 and 4 are the denominators, they are not the same but they are factor of 12. So,
79/3 must be multiplied by 4 = 79 * 4 / 3 * 4 = 316 / 12
41/4 must be multiplied by 3 = 41 * 3 / 4 * 3 = 123 / 12
Step 2. Subtract the numerators and place them above the common denominator
316/12 - 123/12 = 316 - 123 / 12 = 193 / 12
Before we can simplify the fraction, we must divide it by two to get the measurement of each edge of the door.
Steps in dividing fractions.
Step 1. Get the reciprocal of the 2nd fraction.
1st fraction : 193 / 12
2nd fraction : 2 /1 ⇒ reciprocal 1/2
Step 2. Multiply the 1st fraction to the reciprocal of the 2nd fraction
193 / 12 * 1/2 = 193 * 1 / 12 * 2 = 193 / 24
Step 3. Simplify the fraction.
193 / 24 = 8 1/24
