Ques : ​Find 4 numbers in GP in which the sum of the extreme terms is 112 and the sum of the 
middle terms is 48.

Dear student
Let the four terms be a,ar,ar2 and ar3 respectively.A.T.Qa+ar3=112   ...1ar+ar2=48   ....2Dividing eq 1 by eq2, we geta+ar3ar+ar2=112481+r3r+r2=733+3r3=7r+7r23r3-7r2-7r+3=0Also, -1 is a root . So, r+1 is a factorNow, r+13r2-10r+3=0r+13r2-9r-r+3=0r+13rr-3-1r-3=0r+13r-1r-3=0r=-1,3,13But r=-1 not possible  as 1+r3=0Hence possible values  are 13 and 3When r=13Consider ,a+a133=11227a+a27=11228a=3024a=108Thus, numbers are 108,36,12,4When r=3, a+a33=112  27a+a=11228a=112a=4The terms are  4,12,36,108
Regards

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