Question

Isabelle is mixing red paint with blue paint to make purple paint. She adds 3/10 of a fluid ounce of red to 11/15 of a fluid ounce of blue to make1 1/30 fluid ounces of purple. How many fluid ounces of red paint will she need to make 3 fluid ounces of purple paint?
A. 2/5
fluid ounce
B. 11/20
fluid ounce
C. 27/31
fluid ounce
D. 1 13/50
fluid ounces

Answer 1

The answer b-11/20 fluid ounce

Answer 2

Answer: C. 27/31 fluid ounce

Step-by-step explanation:

First, let's turn the mixed number into a fraction:

$1\frac{1}{30}=\frac{(1*30)+1}{30} =\frac{31}{30}$

Then, to solve the problem we can use a simple rule of three:

31/30 ----------3/10

  3  ----------- x

This can be read as: If to make 31/30 fluid ounces of purple you need 3/10 fluid ounces of red, then to make 3 fluid ounces of purple how many fluid ounces of red will you need?

$x=\frac{3*\frac{3}{10} }{\frac{31}{30} } =\frac{\frac{9}{10} }{\frac{31}{30} }=\frac{9*30}{10*31}=\frac{270}{310}=\frac{27}{31}$

So, to make 3 fluid ounces of purple paint, Isabelle will need 27/31 fluid ounces of red paint.