A boy secures 70%, 40% and 60% marks in test papers with 100, 50 and 150 respectively as maximum marks. The percentage of his aggregate is :

60

70% of 100 = $\frac{70}{100}×100=70$ marks

40% of 50 = $\frac{40}{100}×50=20$ marks

60% of 150 = $\frac{60}{100}×150=90$ marks

Total marks secure = 70 + 20 + 90 = 180

Maximum marks = 100 + 50 + 150 = 300

Percentage of marks = \(\frac{180}{300}\) × 100% = 60%