just use what you know about GPs:
ar^3 = ar^2+72
ar^2 = ar+24
So,
ar^2(r-1) = 72
ar(r-1) = 24
Now divide and you have r=3
So, a=4
and the GP is 4,12,36,108
on @ Gp.the 4th term exceed 3rd term by 72 nd 3rd term exceeds 2nd term by 24.fnd the frst four term of the progressn.
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