# The sums of three whole numbers taken in pairs are #11#, #12#, and #17#. What is the middle number (taken in orders)?

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Please help...Thanks!!!

Please help...Thanks!!!

##### 1 Answer

Jul 10, 2018

#### Answer:

#### Explanation:

#"let the 3 numbers be a, b and c, then"#

#a+b=11to(1)#

#b+c=12to(2)#

#a+c=17to(3)#

#"from equation "(1)color(white)(x)b=11-a#

#"from equation "(3)color(white)(x)c=17-a#

#(2)to11-a+17-a=12#

#-2a+28=12rArr-2a=-16rArra=8#

#(1)tob=11-8=3#

#(3)toc=17-8=9#

#"the 3 numbers are "3,color(red)(8)" and "9#