Question

in ten years ,A will be twice as old as B was 10years ago. if A is now 9years older than B .find the present age of B

Answer 1

hi mate

Let B's present age = x years. Then, A's present age = (x + 9) years.
(x + 9) + 10 = 2(x - 10)

 => x + 19 = 2x - 20

 => x =39.

Answer 2

ʜɪ ᴍᴀᴛᴇ

ʟᴇᴛ ʙ's ᴘʀᴇsᴇɴᴛ ᴀɢᴇ = x ʏᴇᴀʀs. ᴛʜᴇɴ, ᴀ's ᴘʀᴇsᴇɴᴛ ᴀɢᴇ = (x + 9) ʏᴇᴀʀs.
(x + 9) + 10 = 2(x - 10)

 => x + 19 = 2x - 20

 => x =39.