1 से 60 तक की संख्याओं में से कितने प्रतिशत संख्याओं के वर्गों का अंतिम अंक 1 होता है?

A person saves 90% of his income. If his expenditure is ₹520, find his income (in ₹).

By how much is 30% of 60 greater than 25% of 40?

By how much is 30% of 50 greater than 35% of 30?