Answer:
15 years
Explanation:
Let Ishaan's age = x years
Ben is 4 times as old as Ishaan.
Hence, Ben's age is 4*x years
6 years ago,Ishaan's age was (x-6) years.
6 years ago,Ben's age was (4x-6) years.
6 years ago, ben was 6 times older than ishaan.
=>
![\[(4x-6) = 6*(x-6)\]](https://img.qammunity.org/2021/formulas/mathematics/middle-school/rvce3ccasorzxqkme598loe2djxypwq05s.png)
=>
=>
![\[6x-4x = 36-6\]](https://img.qammunity.org/2021/formulas/mathematics/middle-school/p13jm1sedmx4b6kia5en5h44x0nqe5gk1s.png)
=>
![\[2x = 30\]](https://img.qammunity.org/2021/formulas/mathematics/middle-school/d5j4i7xaru91hoie94v67un1c21riv20q5.png)
=>
![\[x = (30)/(2)\]](https://img.qammunity.org/2021/formulas/mathematics/middle-school/zptize6jefm3a0iar8z79x36argchmkfp6.png)
=>
![\[x = 15\]](https://img.qammunity.org/2021/formulas/mathematics/middle-school/kg86kkyysy7eoe8s0v1e5iu8uoaew5ctz1.png)