Question 1173746: Corrine is four (4) years older than Minah. Last year, the sum of their ages was 28. How old are they now?
Found 3 solutions by greenestamps, josgarithmetic, ikleyn:
Answer by greenestamps(13200)   (Show Source):
You can put this solution on YOUR website!
With formal algebra....
m = Minah's age
m+4 = Corrine's age (4 years older than Minah)
m-1 = Minah's age last year
m+3 = Corrine's age last year
The sum of their ages last year was 28:
Solve using basic algebra.
Solving informally can give you some good practice with logical reasoning and mental arithmetic:
Last year the sum of their ages was 28, so this year that sum is 30.
Now separate 30 into two ages that differ by 4. One way to do this easily mentally is to see that two identical ages 15 and 15 add to 30; to get two ages that differ by 4 you can add 2 to one of them and subtract 2 from the other to get the answers of 13 and 17.
Answer by josgarithmetic(39618)  (Show Source):
Answer by ikleyn(52788)  (Show Source):
You can put this solution on YOUR website! .
When people solve such problems, they should learn THE LOGIC of the solution,
and that is all what they should know.
The people should not know these formulas --- this TRASH, that @josgarithmetic tries to sell you.
Even do not try to understand or memorize these formulas --- keeping them in your mind is absolutely useless.
THEREFORE, for a sake of your safety, ignore his post and do not load this TRASH into your head / (your mind).
May god saves you from it . . .
Keep your mind clean for more useful/vital tasks of your life.
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@josgarithmetic, every time from now, as I see similar "solution"
from you at this forum, I will issue this message to a visitor.
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