When a number decreased by 10% the result in 63. what is the number?

The number is 69.3 because percent means 0.01, so 10 x 0.01 = 1.1
so 1.1 x 63 = 69.3. you can also do 63 x 10% = 69.3.

All prisms are uniformal shapes meaning that you only need to calculate the base are area and multiply it by the length for example:
Circular Prisms (cylinders)= (area of the base ) (height)=(πr^2)(h)
where h is the height and r is the radius
rectangular prisms = (area of the base) height =(ab) (c)
square prisms (cubes)= (area of the base) height=(S^2)(S)=S^3
where s is any side
triangular prisms =(area of the base) height =(0.5 b h) (l)=0.5 b h l
b is the base of your triangle and h is the height of the triangle and l is the length of the triangular prism