Like Emani’s Haircutting on page 18 of the students’ book, this activity involves finding fractions of a set. The difference is that the total number of the set decreases from question to question as fractions of the set are subtracted.
The students can use the cubes to model the problems. Encourage them to do as much as they can by using their mental strategies supported by their recording. You may need to model the number stories for the students.

Answers to Activity

1. 7 x 3 = 21 bones or 3 + 3 + 3 + 3 + 3 + 3 + 3 = 21
2. a. 21 ÷ 3 = 7 bones or one-third of 21 is 7
b. 21 – 7 = 14 bones
3a. 14 ÷ 2 = 7 bones or half of 14 is 7
b. 14 – 7 = 7 bones
4. a. 1 each (7 ÷ 4 = 1 with 3 remainder)
b. 3 bones