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If Jonah reverses the two digits of his age, divides the resulting number by three, and then adds 20, the result is Jonah’s age. How old is Jonah?

 

No explanation needed, just answer please

 Dec 16, 2020
edited by Guest  Dec 16, 2020
edited by Guest  Dec 16, 2020
 #1
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Let  Jonah's  age  be    10a +  b

 

Reversing the digits  gives    10 b  +  a

 

So  we  have this

 

(10b + a)  / 3  +  20   =  10a + b

 

(10b + a) / 3   =   10a + b   -  20       multiply both sides by 3

 

10b + a   =  30a + 3b -  60      simplify as

 

60  =  29a - 7b

 

Note that this will be  true when   a =  4    and  b  = 8

 

So....his  current age   =  10 (4) + 8  =     48

 

Note  that when he reverses the digits  and divides by 3  he gets 28   adding 20 gives  48  !!!

 

 

cool cool cool

 Dec 16, 2020

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