For every and repeats
Today I can describe a ratio with for every, and multiply the basic pattern to find the total.
A Look back3 min
- 1.
3 rows of 8 counters. 3 × 8 =
- 2.
Which number is a factor of 36?
57910 - 3.
Add the coins. How many pence altogether?
B Watch me, then you4 min
Ola threads beads in a repeat. For every 2 red beads there are 3 blue beads.
2 red and 3 blue make one basic pattern of 5 beads.
Repeat it 4 times: 5 × 4 = 20 beads.
So 20 beads are 8 red and 12 blue.
- 1.
The basic pattern is 2 red and 3 blue. In 3 repeats, how many red beads?
C Your turn5 min
The pattern is always 2 red and 3 blue. Only the number of repeats changes.
- 1.
2 repeats. How many blue beads?
- 2.
4 repeats. How many blue beads?
- 3.
5 repeats. How many blue beads?
- 4.
10 repeats. How many blue beads?
Say it out loud: What changed in each row? What stayed the same, and how did that help you?
D Spot the mistake2 min
- 1.
For every 2 red beads there are 3 blue beads. How many blue beads go with 10 red beads?
E Think deeper4 min
- 1.
Ari has 24 beads in a red and blue pattern. Write every basic pattern size from 2 to 24 that fits 24 beads exactly.