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If twice the present age of pedro is decreased from petra's age 5 years ago, the result is 4. Nine times pedro's age 3 years ago exceeds 4 times Petra's present age by 4. What are their ages last year?

Nov 15, 2015

#1
+97576
+10

I saw this one get answered yesterday (or earlier today) by 2 different guests.  Didn't you like their answers?

OR is it just that you did not look for ages and notw you cannot find your question?  If you were a member it would have been automatically put in your watchlist and you would have been able to find it really easily!

Let Pedro's age today be Y

and  Petra's age today be   X

If twice the present age of pedro (2Y) is decreased from petra's age 5 years ago (X-5), the result is 4.

(X-5) - 2Y = 4

X-5 - 2Y = 4

X - 2Y = 9     times 4 because I am going to use it with (2) below.

4X - 8Y = 36    (1)

Nine times pedro's age 3 years ago [9(Y-3)]   exceeds 4 times Petra's present age [ 4X]  by 4.

9(Y-3) - 4X = 4

9Y-27 - 4X = 4

9Y - 4X = 31

- 4X +9Y = 31  (2)

(1)+(2)

0+Y = 67

Pedro is 67 now

4X-8*67=36

4X=36+536

4X=572

X=143

Petra is 143 and Pedro is 67

check

If twice the present age of pedro (2Y) is decreased from petra's age  years ago  (X-5) , the result is 4.

138 - 2*67 = 138-134 = 4 good

Nine times pedro's age 3 years ago [9(Y-3)] 9*64 = 576  exceeds 4 times Petra's present age [ 4X=4*143=572]  by 4.

576-572=4 good

So that is correct I believe.

So last year Petra was 142 and Pedro was 66 years old.   Maybe they are sea turtles. Sea turtles live a long time.

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Here is the earlier answer It was only a few post back so maybe the answer did not suit you.  It is different from what I got.  Words such as these can be difficult to interprete.

Nov 15, 2015
edited by Melody  Nov 15, 2015

#1
+97576
+10

I saw this one get answered yesterday (or earlier today) by 2 different guests.  Didn't you like their answers?

OR is it just that you did not look for ages and notw you cannot find your question?  If you were a member it would have been automatically put in your watchlist and you would have been able to find it really easily!

Let Pedro's age today be Y

and  Petra's age today be   X

If twice the present age of pedro (2Y) is decreased from petra's age 5 years ago (X-5), the result is 4.

(X-5) - 2Y = 4

X-5 - 2Y = 4

X - 2Y = 9     times 4 because I am going to use it with (2) below.

4X - 8Y = 36    (1)

Nine times pedro's age 3 years ago [9(Y-3)]   exceeds 4 times Petra's present age [ 4X]  by 4.

9(Y-3) - 4X = 4

9Y-27 - 4X = 4

9Y - 4X = 31

- 4X +9Y = 31  (2)

(1)+(2)

0+Y = 67

Pedro is 67 now

4X-8*67=36

4X=36+536

4X=572

X=143

Petra is 143 and Pedro is 67

check

If twice the present age of pedro (2Y) is decreased from petra's age  years ago  (X-5) , the result is 4.

138 - 2*67 = 138-134 = 4 good

Nine times pedro's age 3 years ago [9(Y-3)] 9*64 = 576  exceeds 4 times Petra's present age [ 4X=4*143=572]  by 4.

576-572=4 good

So that is correct I believe.

So last year Petra was 142 and Pedro was 66 years old.   Maybe they are sea turtles. Sea turtles live a long time.

----------------------------------------------------------------------------

Here is the earlier answer It was only a few post back so maybe the answer did not suit you.  It is different from what I got.  Words such as these can be difficult to interprete.