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Sixteen and seventeen
Discover Mathematics: Chapter 4
GoalCount, read and write 16 and 17, and show them on two ten-frames.
New words
sixteen · ten and six moreseventeen · ten and seven morerow · things side by side in a line
Explanation
Sixteen is ten and six more. Seventeen is ten and seven more. On two ten-frames, sixteen is a full frame and six counters on the second frame. Seventeen is a full frame and seven counters on the second frame. Seventeen comes right after sixteen. We write both numbers with two digits: the 1 on the left shows one ten, and the digit on the right shows the extra ones.
Worked examples
Seventeen is a full ten-frame and 7 counters on the second frame.
Rahma counts 16 pebbles in two rows of 8: 1, 2, 3, up to 16.
Mina has 10 stars in one row and 7 stars in another row. Together there are 17 stars.
Class activity
Sixteen beans. Count 16 beans into two rows of 8 and count them all. Slide them into one long line and count again: it is still sixteen. Add one more bean and say seventeen.
Practice
1
How many pineapples are there?
16
2
How many rabbits are there?
17
3
Here are 10 flowers and 6 more flowers. How many flowers are there in all?
16
4
What number comes just before 17?
16
5
Which number is greater, 16 or 17?
17