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1 vote
Megan is 5 years older than Sandy. If four years ago Megan was three years less than three times Sandys age, how old is Sandy now ?

User Azulflame
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5.8k points

2 Answers

2 votes
Sandy is currently 8 years old.

Start by using x for Sandy's current age and x + 5 for Megan's current age.

Since we know the above, we can find their age's as of 4 years ago as both of those minus 4. So Sandy 4 years ago was x - 4 years old and Megan was x + 1 years old.

Now we can set up an equation that shows that Megan's age 4 years ago was equal to Sandy's age 4 years ago times 3 minus 3.

x + 1 = 3(x - 4) - 3
x + 1 = 3x - 12 - 3
x + 1 = 3x - 15
x + 16 = 3x
16 = 2x
8 = x

Which is Sandy's current age.
User Rey Libutan
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5.9k points
4 votes
Let the present age of Sandy be 'x' .

So, present age of Megan will be = x + 5

Therefore age of Sandy four years ago = x - 4
Age of Megan four years ago = x + 5 - 4 = x + 1


It is given that four years ago Megan was three years less than three times Sandys age.

So, an equation can be formed as follows;


= > x + 1 = 3(x - 4) - 3 \\ \\ = > x + 1 = 3x - 12 - 3 \\ \\ = > 1 + 15 = 3x - x \\ \\ = > 2x = 16 \\ \\ = > x = 8
Therefore the present age of Sandy is 8 years.
User Makpoc
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6.4k points