WAEC Mathematics 2024 Paper

Concept:Multiplying numbers in standard form involves multiplying the coefficients and adding the powers of ten.Explanation:Write the expression as $(3.4 \times 10^{-5}) \times (7.1 \times 10^8)$.Group the decimal parts and powers of ten separately.$= (3.4 \times 7.1) \times (10^{-5} \times 10^8)$Multiply the coefficients: $3.4 \times 7.1 = 24.14$.Add the exponents: $10^{-5} \times 10^8 = 10^{-5+8} = 10^3$.So the product becomes $24.14 \times 10^3$.Standard form requires the coefficient to lie between $1$ and $10$.Rewrite $24.14$ as $2.414 \times 10^1$.Then $24.14 \times 10^3 = (2.414 \times 10^1) \times 10^3$.Adding exponents gives $10^1 \times 10^3 = 10^4$.Hence, the product is $2.414 \times 10^4$.Answer:$2.414 \times 10^4$ (Option C).