Same whole, different parts
Today I can explain how different parts can make the same whole.
A Look back3 min
- 1.
6 + 4 + 3 =
- 2.
4 × 5 =
- 3.
50 − 20 =
B Watch me, then you4 min
This made-up rod set has no numbers on the rods. The key below only tells you how long each colour is, in cm: white 1, red 2, green 3, purple 4, yellow 5, black 7, brown 8, blue 9, orange 10.
Orange is the whole. Brown and red are the parts.
Laid end to end, brown and red match orange exactly.
So orange is equivalent to brown + red.
- 1.
Blue and white laid end to end match one other rod exactly. Which rod is the whole? Circle it.
orangebluewhite
C Your turn6 min
Use the key from the last part. Each row changes one thing. Keep the orange rod as the whole.
- 1.
How many red rods fit exactly along one orange rod?
- 2.
How many yellow rods fit exactly along one orange rod?
- 3.
Brown rod plus which rod fits exactly along orange? Circle the colour that fits.
redpurpleblue - 4.
Black rod plus which rod fits exactly along orange? Circle the colour that fits.
greenyellowpurple
Say it out loud: What stayed the same in every row, and what changed?
D Spot the mistake3 min
- 1.
How long are brown and red together, in cm?
E Think deeper3 min
- 1.
Make a whole orange rod from three or more rods. Write it as an equation using + or ×. Explain how you know it fits.