Which is more economical purchasing the economy size of a detergent at 7 kilograms for $7.15 or purchasing the regular size at 790 grams for 60¢? Select the correct choice below and fill in the answer box to complete your choice.
(Round to four decimal places as needed.)
O A. Purchasing the economy size is more economical because the economy size costs $ less per gram.
O B. Purchasing the regular size is more economical because the regular size costs $less per gram