AMC 8

The average of five numbers is 12. When one number is removed, the average of the remaining four is 11. What number was removed?

How many three-digit numbers have digits that sum to 4?

A rectangle's length increases by 20% and its width decreases by 20%. By what percent does the area change? (Signed percent, e.g. -5.)

What is 20% of 15% of 200?

What is the measure, in degrees, of the smaller angle between the hands of a clock at 3:30?

Five consecutive integers sum to 100. What is the largest of them?

On a grid you may move only right or up. How many paths go from (0,0) to (3,3)?

How many squares of any size are there on a 4×4 grid of unit squares?

What is 1/2 + 1/3 + 1/6?

Three bells ring every 6, 8 and 12 minutes. They ring together now. In how many minutes will they next ring together?

What is the mean of the first 10 positive integers? (Fraction.)

One pipe fills a tank in 3 hours and another fills it in 6 hours. Working together, how many hours do they take?

A car drives 60 km at 30 km/h, then returns the same 60 km at 60 km/h. What is the average speed for the whole trip, in km/h?

How many integers between 100 and 300 are divisible by 7?

A price rises 25% and then falls 20%. By what percent has it changed overall? (Signed percent.)

A 3×3×3 cube is painted on all outer faces and cut into unit cubes. How many unit cubes have exactly two painted faces?