Question

Find the product of 20x9x5. Tell which property you used

Answer 1

900


20×5×9=(20×5)×9=100×9=900

Answer 2

$20\times9\times5\\\\Use\ Commutative\ property\ a\times b=b\times a\\\\20\times5\times9=(20\times5)\times9=100\times9=\boxed{900}$