## College Algebra 7th Edition

(a) $186,000,000,000=1.86\times 10^{11}$ (b) $0.0000003965=3.965\times 10^{-7}$
(a) To write the number in scientific notation, we count the number of decimal places to move to the right after the first digit: $186,000,000,000=1.86\times 10^{11}$ (b) To write the number in scientific notation, we count the number of decimal places to move to the left from the digit "3": $0.0000003965=3.965\times 10^{-7}$