Quantitative Aptitude - Arithmetic Ability Questions

In the following question, select the odd word from the given alternatives.

A boy multiplied 987 by a certain number and obtained 559981 as his answer. If in the answer both 98 are wrong and the other digits are correct, then the correct answer would be ?? please explain in detail

ln a company all Mondays and Sundays are offs. If a month starts with a Monday and has 31 days then how manys offs will be there in that month?

Buy at 30 cell at 50. What is the profit percentage?

If a3+ b3 = 341 and ab = 30, then what is the value of a + b?

A man buys a watch for Rs1950 in cash and sells it for Rs 2200 at a credit of 1 yr. The rate of interest is 10% per annum. Then he gains or loose how much amount?

Weights of two friends A and B are in the ratio of 7 : 8. A’s weight increases by 10% and the total weight of A and B increase by 20%. What is the percentageincrease in the B’s weight?

A man lent a sum of money at the rate of simple interest of 4%. If the interest for 8 years is Rs 340 less than the principal, the principal is