Question 1153529

let Jeremy's age be {{{x}}}

if Jeremy's grandfather is four times as old as he is,grandfather's age is {{{4x}}}

if the sum of their ages is {{{90}}}, we have

{{{x+4x=90}}}

{{{5x=90}}}

{{{x=90/5}}}

{{{x=18}}}->Jeremy's age

Jeremy's grandfather will be {{{4x=4*18=72}}}

answer:	
	D.	{{{72}}}