Question

question 2 (1 point) listen which is correct if 15,390,000 is rounded to two significant figures? a) 15,000,000 b) 15,400,000 c) 1.5 × 10⁻⁷ d) 15 e) 1.5 × 10⁸

Explanation:

Step1: Identify first two sig figs

The first two significant figures of 15,390,000 are 1 and 5.

Step2: Check next digit for rounding

The digit after 5 is 3, which is <5, so we keep 5 unchanged.

Step3: Convert to proper form

15,390,000 rounded to two sig figs is 15,000,000, which can also be written as $1.5 \times 10^7$. Now match with options:

• Option a: 15,000,000 has two significant figures (the trailing zeros are placeholders, and the 1 and 5 are the significant digits).
• Option c: $1.5 \times 10^{-7}$ is $0.00000015$, which is not equal to 15,000,000.
• Option e: $1.5 \times 10^8$ is 150,000,000, which is 10 times larger than the original number.

Answer:

a) 15,000,000