Problema Solution
Which is more economical, purchasing the economy size of detergent at 31 kg for $3.15 or purchasing the regular size at 720 g for 60 cents?
Answer provided by our tutors
economy size of detergent: 31 kg of detergent costs $3.15 => 1 kg detergent costs $(3.15/31)
since 1 kg = 1000 g and 1$ = 100 cents we have
1000 g of detergent costs (3.15/31)*100 cents or
1g of detergent costs (3.15/31)*100/1000 = 3.15/310 cents
regular size detergent: 720 g for 60 cents thus 1 g costs 60/720 cents
lets compare 3.15/310 and 60/720
60/720 = 30/310 > 3.15/310
the economy size of detergent is more economical.