sergio bought 5 new binders for $4.50 each. he also bought 20 pencils six pencils cost $3.60. what is the total amount sergio spent on the binders and pencils?

!! 10 ! a westbound jet leaves central airport traveling 635 miles per hour. at the same time, an eastbound plane departs at 325 miles per hour. in how many hours will the planes be 1900 miles apart?

Ageologist had two rocks on a scale that weighed 4.6 kilograms together. rock a was 0.5 of the total weight. how much did rock a weigh?

Write the percent as a fraction or mixed number in simplest form. 0.8%