Question

snow day #3 assignment- optional
an expression is shown.
$2.1 \times 10^3 + 4.3 \times 10^4$
$\bigcirc\\ 2.53 \times 10^4$
$\bigcirc\\ 2.53 \times 10^5$
$\bigcirc\\ \text{hand icon} \times 10^3$
$\bigcirc\\ 6.4 \times 10^9$

Explanation:

Step1: Rewrite terms to same exponent

Convert $2.1 \times 10^3$ to $0.21 \times 10^4$

Step2: Add the coefficients

$0.21 \times 10^4 + 4.3 \times 10^4 = (0.21 + 4.3) \times 10^4$

Step3: Simplify the sum

$4.51 \times 10^4 = 4.51 \times 10^4$ (rewritten as $4.51 \times 10^4$, which matches the obscured option's structure)

Answer:

(Obscured option). $4.51 \times 10^4$