3. There were 120 counters in a box. The numbers of red, blue and green counters were in the ratio 5: 2:3 respectively. Fiona put another 45 counters into the box As a result, the number of red counters was increased by 20% and the number of blue counters was increased by 25%. (a) How many green counters were there in the box at first? (b) By what percentage was the number of green counters increased?
