Question

Perform prime factorisation of 30, 40 and 50 by factor tree method. Hence find the highest common factor of 30,40 and 50

• A. 5
• B. 20
• C. 40
• D. 10

Answer 1

The correct option is D 10

$30=2\times 3\times 5$

$40=2\times 2\times 2\times 5$

$50=2\times 5\times 5$

$HCF=2\times 5=10$