+0  
 
0
88
3
avatar

A, B, C, D are distinct positive integers such that AB = 60, CD = 60, and A - B = C + D.  What is the value of A?

 May 17, 2020
 #1
avatar
0

 

A = 20 

B =   3        A – B  =  20 – 3  =  17 

 

C = 12  

D =   5        C + D  =  12 + 5  =  17  

.

 May 17, 2020
 #2
avatar+74 
+2

In this problem because A B = C D, A has to be pretty big. So we start trying some cases in which A is big. First we try A = 10, so B has to equal 6. 10 -6 = 4. No 2 positive integers that multiply to 60 add up to 4. Next, we try 15 if A is 15 then B is 4,15 - 4 = 11 the smallest factor sum is 6 and 10 which adds up to 16 so that isn't right. Finally, we try A = 20 B = 3, 20 - 3 = 17. 12*5 = 20 and they add to 17 so we have found the answer. A = 20.

 May 18, 2020
 #3
avatar
0

Which is 2/3 of 9

 May 18, 2020

51 Online Users

avatar