an object traveling at a steady speed of 10 and 1 over 10.howlong will it take the object to travel 1 and 9 over 10 ? first round to nearest interger to find the estimated answer. then find the exact answer.

Last month, a 770 g box of cereal was sold at a grocery store for $3.10. however, this month, the cereal manufacturer launched the same cereal in a 640 g box, which is being sold at $2.50. what is the percent change in the unit price?