1. Multiply. (i) 5 7 × 3 8

Given, 5 7 × 3 8 , Multiplication of rational numbers is equal to the product of numerators divided by the product of denominators. We know that, a b × c d = a c b d So, = 5 7 × 3 8 = 5 × 3 7 × 8 = 15 56 Therefore, the product of two given rational numbers is 15 56 .

1. Multiply. (ii) 9 17 × 51 23

Given, 9 17 × 51 23 , Multiplication of rational numbers is equal to the product of numerators divided by the product of denominators. We know that, a b × c d = a c b d So, = 9 17 × 51 23 = 9 × 51 17 × 23 = 9 × 3 23 = 27 23 Therefore, the product of two given rational numbers is 27 23 .

1. Multiply. (iii) 15 × 3 105

Given, 15 × 3 105 , Multiplication of rational numbers is equal to the product of numerators divided by the product of denominators. We know that, a b × c d = a c b d So, = 15 × 3 105 = 15 × 3 105 = 3 × 3 21 = 3 7 Therefore, the product of two given rational numbers is 3 7 .

1. Multiply. (iv) - 83 27 × 0

Given, - 83 27 × 0 , Multiplication of rational numbers is equal to the product of numerators divided by the product of denominators. We know that, a b × c d = a c b d So, = - 83 27 × 0 = 0 Therefore, the product of two given rational numbers is 0 .

1. Multiply. (v) 0 × 111 89

Given, 0 × 111 89 , Multiplication of rational numbers is equal to the product of numerators divided by the product of denominators. We know that, a b × c d = a c b d So, = 0 × 111 89 = 0 Therefore, the product of two given rational numbers is 0 .

1. Multiply. (vi) - 6 25 × 50 24

Given, - 6 25 × 50 24 , Multiplication of rational numbers is equal to the product of numerators divided by the product of denominators. We know that, a b × c d = a c b d So, = - 6 25 × 50 24 = - 6 × 50 25 × 24 = - 1 × 50 25 × 4 = - 1 × 2 1 × 4 = - 1 2 Therefore, the product of two given rational numbers is - 1 2 .

1. Multiply. (vii) - 5 9 × - 9 5

Given, - 5 9 × - 9 5 , Multiplication of rational numbers is equal to the product of numerators divided by the product of denominators. We know that, a b × c d = a c b d So, = - 5 9 × - 9 5 = - 1 × - 1 1 × 1 = 1 Therefore, the product of two given rational numbers is 1 .