The average newborn weighs 7.5 pounds. About 4.1×10^6 babies are born in the United States every year. What is the approximate total weight in pounds of all the babies born in the U.S. in a year? Write the answer in scientific notation, expressed to the exact decimal place.
____pounds
The total weight of all the babies born in the U.S. in a year can be calculated by multiplying the average weight of a newborn by the total number of babies born:
7.5 pounds/baby * 4.1×10^6 babies = 30.75×10^6 pounds
To express this answer in scientific notation, we first need to combine the numbers before the "x10^" and then adjust the decimal point to have one non-zero digit to the left of the decimal point:
30.75×10^6 = 3.075×10^7
Therefore, the approximate total weight of all the babies born in the U.S. in a year is 3.075×10^7 pounds.