You earned a 90% on a science test. you answered 20 questions correctly. how many questions were on the test?

Arestaurant chef made 1 1/2 jars of pasta sauce. each serving of pasta requires 1/2 of a jar of sauce. how many servings of pasta will the chef be bale to prepare using the sauce?

One astronomical unit (1 au) is about 1.496 alt tag missing. kilometers. if you wrote this number of kilometers in regular decimal notation (for example, 528 and 3,459 are written in regular decimal notation), how many zeros would your number have?

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?