Basic Mathematics
# Ratio, Rate, and Proportion

It took Marie 10 minutes to cut a board into 2 pieces. If she works just as fast, how long will it take for her to cut another board into 3 pieces? (Assuming you can only cut any piece into half)

At Pierre & co, the worker Pierre can craft a guitar in 4 days, while the young Paul can craft a guitar in 8 days.

If they were to work together, how many days will it take for them to craft 6 guitars?

If 5 hens need 5 days to hatch 5 eggs, how many days would it take 100 hens to hatch 100 eggs?

Beckham wants to build a model of the Solar system. If he decided that the earth would be represented by a regulation sized soccer ball (roughly spherical and approximately 11 cm radius), which of the following would be the best representation of the moon?

Note: the actual radius of the earth and moon are approximately 6368 km and 1738 km, respectively.

Principal Nigel wanted to figure out the height of the 7th graders, and transform it into a problem for the 6th graders. After hours, of hard work the 6th graders couldn't figure it out. Can you help them? Well here it is:

7th graders' average height for the girls is 54 inches. The average height for the boys is 55 inches. If the ratio of girls to boys is 7 to 6, what is the average height of all the students?