Ratio of nos. = 7:8
Let nos. be 7x and 8x respectively.
If 3 is added to each of them, the nos. are 7x+3 and 8x+3
And, Hence their ratios becomes (7x+3):(8x+3).
But Acc. to question, when 3 is added, the ratios becomes 8:9.
⇒63x - 64x= 24 - 27
⇒-x = -3
Hence nos are 7x=7*3=21 & 8x=8*3=24. (Ans)