SOLUTION: Simplify 4a-2b+2a-3b. The average age of a mother and are 3 children is 10years. If the ages of the children are 1,4 and 7years. Find the age of their mother.

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Question 177237: Simplify 4a-2b+2a-3b. The average age of a mother and are 3 children is 10years. If the ages of the children are 1,4 and 7years. Find the age of their mother.
Answer by gonzo(654) (Show Source):
You can put this solution on YOUR website!
to get the average, you take the sum of the ages and divide by the number of ages:
let x = the age of the mother:
(1 + 4 + 7 + x)/ 4 = 10
(x + 12)/4 = 10
multiply both sides of the equation by 4 to get:
x + 12 = 40
subtract 12 from both sides of the equation to get:
x + 12 - 12 = 40 - 12
simplify to get:
x = 28
mother should be 28 years old.
1 + 4 + 7 + 28 = 40 / 4 = 10
looks good.
mother is 28 years old.
to simplify 4a - 2b + 2a - 3b do the following:
combine like terms:
4a + 2a = 6a
-2b - 3b = -5b
simplified term is:
6a - 5b