Hello!
I take that the "/" was meant to be a fraction. There fore, your answer would be

.
Enjoy.
~Isabella
Answer:
the answer is 45
Step-by-step explanation:
Add digit by digit, from the right, just like any number, except that if it adds to 2, then put a zero and carry one (instead of carrying when it adds to 10 or more).
Example: < means carry, decimal equivalent for checking
1011+1111
1 0 1 1 (8+2+1=11)
+ 1 1 1 1 (8+4+2+1=15)
---<---<----<----<----
1 1 0 1 0 (16+8+2=26)
Proceeding similarly,
a. 10101111+11011011 = 110001010 (394)
b. 10010111+11111111 = 110010110 (406)
c. 01110101+10101100 = 10010001 (289)
Paper he needs = total surface area
So to break it down into 2D shapes, that prism has 2 2D triangles, and 3 2D rectangles of different sizes.
The triangles are the same size, since you have 2, just multiply 2 by the formula for the area of a triangle: 1/2(base)(height) which is 2x1/2(5)(12) = 60
Next you'll need the area of all the rectangles: length x width. which would be (5 x 5) + (13 x 5) + (12 x 5) = 150
So the total amount of wrapping paper he'd need is 150mi^2