JACKIE IS 8 YEARS OLDER THAN MONA. IF 9 YEARS AGO SHE WAS THREE TIM...

Lớp 3 Toán ĐỀ THI TOÁN RSM VÀ IMC DÀNH CHO HỌC SINH LỚP 3 ĐẾN LỚP 8

9. Jackie is 8 years older than Mona. If 9 years ago she was three times as old as Mona was, how old is Jackie now?