Answer:
75 cubic units
Step-by-step explanation:
Bottom layer of a rectangular prism is made up of 15 unit cubes.
Therefore, area of the 15 unit cubes = 15(area of the base of one unit cube)
= 15(1)²
= 15 unit²
Number of layers of unit cubes in the rectangular prism = 5
So the height of the prism = 5 units
Volume of the prism = (Area of the base) × Height
= 15 × 5
= 75 cubic unit
using the LCD method.... well, there are a couple of ways, but let's simply add them up.
well, the denominators are 5x and 2x... so the only LCD will just be 10x, since it's divisible by both, so let's use that one.
![\bf \cfrac{2}{5x}+\cfrac{7}{2x}=1\implies \stackrel{\textit{LCD of 10x}}{\cfrac{(2)2~~+~~(5)7}{10x}}=1\implies \cfrac{4+35}{10x}=1\implies \cfrac{39}{10x}=1 \\\\\\ 39=10x\implies \cfrac{39}{10}=x\implies 3\frac{9}{10}=x](https://tex.z-dn.net/?f=%5Cbf%20%5Ccfrac%7B2%7D%7B5x%7D%2B%5Ccfrac%7B7%7D%7B2x%7D%3D1%5Cimplies%20%5Cstackrel%7B%5Ctextit%7BLCD%20of%2010x%7D%7D%7B%5Ccfrac%7B%282%292~~%2B~~%285%297%7D%7B10x%7D%7D%3D1%5Cimplies%20%5Ccfrac%7B4%2B35%7D%7B10x%7D%3D1%5Cimplies%20%5Ccfrac%7B39%7D%7B10x%7D%3D1%20%5C%5C%5C%5C%5C%5C%2039%3D10x%5Cimplies%20%5Ccfrac%7B39%7D%7B10%7D%3Dx%5Cimplies%203%5Cfrac%7B9%7D%7B10%7D%3Dx)
Answer:
the answer to the question is 3.2