NCERT Class 10th Mathematics Chapter 1 Real number Exercise 1.1

The exercise includes the use of Euclids division lemma.

Que1

Use Euclid division algorithm to find HCF of:

1: 135 and 225

2:196 and 38220

3: 867 and 225

Solution:

1: 135 and 225

Here we can see that 225 is greater than 135. Therefore applying Euclid division algorithm we can have,

225 = 135*1 +90

Again remainder 90 is not equal to zero, so we can apply Euclid division lemma for 90 and we get,

135=90*1+45

Again 45 is not equal to zero, repeating the step we have,

90=45*2+0

Here we get remainder zero, and in the last step divisior is 45 therefore we get our hcf.

Hence HCF of 135 and 225 is 45.

2: 196 and 38220

Here 38220 > 196 therefore by applying division lemma and taking 38220 as divisor, we get

38220 = 196*195+0

Remainder is zero.

The HCF is 196.

3: 867 and 225

Here 867 > 225 ,therefore by applying division lemma and taking 867 as divisor we get,

867 =225*3+102

But we don’t get remainder zero therefore by applying Euclid division algorithm and taking 102 as a divisor we get,

225 =102*2+51

Again remainder is not equal to zero so repeating the process we get,

102 = 51*2+0

Now we get the remainder zero.

Hence HCF is 51.