Secondary School (English Medium) (5 to 8) इयत्ता ७ - CBSE Question Bank Solutions for Mathematics

Which of the following is the multiplicative identity for an integer a?

11 × (–5) = – (_____ × _____) = _____.

______ is the multiplicative identity for integers.

We get additive inverse of an integer a when we multiply it by ______.

______ × (–1) = 47

88 × ______ = –88

(–1) is not a multiplicative identity of integers.

Match the following:

Below u, v, w and x represent different integers, where u = –4 and x ≠ 1. By using following equations, find each of the values:
u × v = u
x × w = w
u + x = w

1. v
2. w
3. x

Explain your reasoning using the properties of integers.

Gayatri’s income is ₹ 1,60,000 per year. She pays 15% of this as house rent and 10% of the remainder on her child’s education. The money left with her is ______.

The interest on ₹ 30000 for 3 years at the rate of 15% per annum is ______.

Amount received on ₹ 3000 for 2 years at the rate of 11% per annum is ______.

Interest on ₹ 12000 for 1 month at the rate of 10% per annum is ______.

Rajni and Mohini deposited ₹ 3000 and ₹ 4000 in a company at the rate of 10% per annum for 3 years and `2 1/2` years respectively. The difference of the amounts received by them will be ______.

The sum which will earn a simple interest of ₹ 126 in 2 years at 14% per annum is ______.

Interest on ₹ 3000 at 10% per annum for a period of 3 years is ______.

Amount obtained by depositing ₹ 20,000 at 8% per annum for six months is ______.

Interest on ₹ 12500 at 18% per annum for a period of 2 years and 4 months is ______.

Interest = `(P xx R xx T)/100`, where T is ______ R% is ______ and P is ______.

The difference of interest for 2 years and 3 years on a sum of ₹ 2100 at 8% per annum is ______.