Level 1
A group of 3 boys and 7 girls shared a bag of pencils. Each of them took 4 pencils. There were 15 pencils left. What is the total number of pencils in the box at first?
Level 3
At a factory, Bryan could assemble 7 robots in a day while Francis could assemble 4 more robots than him in a day. If Francis was absent for 3 days, how many days would he need to assemble 17 more robots than Bryan?
Level 2
Heather went to the gym once every 4 days while Vicky went to the same gym once every 6 days. They became friends after meeting each other at the gym on a Saturday. Which would be the next earliest day that they would meet each other again at the gym? Give the answer in number. (Eg Mon = 1; Tue = 2)