The correct answer is: [A]: " 15.75 * 10⁷ " . ___________________________________________________ The problem is: ___________________________________________________ "What is: "(2.5 * 10²) (6.3 * 10⁵)" (in scientific notation)? ___________________________________________________ (2.5 * 10²) (6.3 * 10⁵) =
2.5 * 10² * 6.3 * 10⁵ =
2.5 * 6.3 * 10² * 10⁵
= 2.5 * 6.3 * 10⁽² ⁺ ⁵) =
= 2.5 * 6.3 * 10⁷ ; ______________________________________________________ Note the following property of exponents: ______________________________________________________ xᵃ * xᵇ = x ⁽ᵃ ⁺ ᵇ⁾ ; ______________________________________________________ Thus: 10² * 10⁵ = 10⁽² ⁺ ⁵) = 10⁷ ; ______________________________________________________ So; we have: ______________________________________________________ 2.5 * 6.3 * 10⁷ ;
