एक संख्या को 32% बढ़ाने पर प्राप्त मान और उसी संख्या को 28% घटाने पर प्राप्त मान के बीच का अंतर 180 है। संख्या ज्ञात कीजिए।

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?