Which of the following numbers are correctly expressed in ordinary decimal form?
i.6.21 × 10⁵ = 621,000
ii.7.28 × 10⁶ = 0.00000728
iii.9.03 × 10^-4 = 0.000903
iv.1.12 × 10^-3 = 1120

Question

Quizplus · Accepted Answer

i. 6.21 x 10^111111111111111 (cannot have a negative exponent for ordinary decimal form)
ii. 7.28 x 10^-16 (correctly expressed in scientific notation and converted to ordinary decimal form)
iii. 9.03 x 10^-4 (correctly expressed in scientific notation and converted to ordinary decimal form)
iv. 1.12 x 10^-3 (correctly expressed in scientific notation and converted to ordinary decimal form)

Therefore, only i and iii are incorrect and the correct answer choice is B.

Which of the Following Numbers Are Correctly Expressed in Ordinary