Numbers up to 50
Primary 1 · Mathematics
Numbers up to 50
Lesson 5 of 6
12 min
Let's begin
Keza and Gatete each pick maize cobs at home.
Keza makes 3 bundles and has 1 cob left over. Gatete makes 2 bundles and has 9 left over.
Gatete says he has more. Is he right? Today you will find out.
Keza has 31. Gatete has 29.
Look at the tens first. Always the tens first.
31 has 3 bundles. 29 has 2 bundles.
Three bundles beat two bundles. So 31 is bigger.
Careful! The 9 in 29 looks big. But loose ones can never beat a whole bundle.
Gatete was wrong. Keza has more maize.
Compare 34 and 37.
Both have 3 bundles. The tens are equal.
Now look at the loose ones: 4 and 7.
7 is more than 4. So 37 is bigger.
12 and 21 both use a 1 and a 2. They are not the same number.
12 is 1 bundle and 2 loose ones.
21 is 2 bundles and 1 loose one.
Tens first: two bundles beat one bundle. So 21 is bigger.
The sign > says is bigger than.
The sign < says is smaller than.
The wide open side always looks at the bigger number.
31 > 29 is read: thirty-one is bigger than twenty-nine.
18 < 25 is read: eighteen is smaller than twenty-five.
When two numbers are the same we use =. So 40 = 40.
Put these in order: 45, 14, 41, 50.
Count the bundles in each one: 4, 1, 4, 5.
14 has only 1 bundle, so it is the smallest.
45 and 41 both have 4 bundles. Look at the loose ones: 1 is less than 5.
Smallest to biggest: 14, 41, 45, 50.
Tip
Tens are the boss
Cover the loose ones with your finger. Count the bundles first.
Only when the bundles are equal do you look at the loose ones.
Which is bigger? Count the tens first.
Answer each one, then tap Show answer to check.
Which is bigger, 18 or 25?
Answer: 25. Two bundles beat one bundle.
Which is bigger, 36 or 34?
Answer: 36. The tens are the same, and 6 ones beat 4 ones.
Which is bigger, 21 or 12?
Answer: 21. It has 2 bundles, and 12 has only 1.
Write bigger or smaller: 47 is ___ than 50.
Answer: smaller. 47 has 4 bundles, 50 has 5.
Put these in order, smallest first: 30, 13, 33.
Answer: 13, 30, 33. One bundle, then three bundles with nothing loose, then three bundles and 3 loose.
What you learned today
Quick check
Which number is the biggest?
