एक संख्या दूसरी संख्या से 50% अधिक है। तो दूसरी संख्या पहली संख्या से कितने प्रतिशत छोटी 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?