Step 1: Find the Lowest Common Multiple between the denominators.
Step 2: Multiply the numerator and denominator of each fraction by a number (the one that will get them to the lcm) so that they have the LCM as their new denominator.
Step 3: Add or subtract the numerators and keep the denominator the same.
Answer: red marble 7 out of 20 : 7/20 : 0.35: 35%
Step-by-step explanation:
We can create a formula first.
X will be the unknown number
840= 357+x
-357 -357
483 = x
Hope this helps
Answer: 
Step-by-step explanation:
Given:

To make
the subject of the formula means that we want to make
to stand alone , the first thing to do is to multiply through by 1/4a , that is

take the square of both sides:

Angle AQB is x = 90
Angle ASB is x = 90
Angle ALB is x = 90
Angle ATB is x = 90
Angle ARB is x = 90
<span>BWD is x < 90</span>