Question

Evaluate the GCD of 28, 38, 48 and 58.

Answer 1

Let's make the Factor Tree of each given number.

$\underset{–}{28}$

$\underset{–}{38}$

$\underset{–}{48}$

$\underset{–}{58}$

$\to 28=2\times 2\times 7$
$\to 38=2\times 19$
$\to 48=2\times 2\times 2\times 2\times 3$
$\to 58=2\times 29$

The common factor among these is $2.$
$\therefore$ GCD is $2.$