Look at these sequences. What is happening? 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 10, 20, 30, 40, 50, 60, 70, 80, 90, , 200, 300, 400, 500, 600, 700, 800, 900, 1000
Counting on in tens. Counting on in tens means adding ten on to the previous number in the sequence. Practice: 10, 20, 30, …, …, …, …, …, …, …, …, Now try starting at , 110, …., ….., ….., ….., …..,
Counting back in tens. Counting back in tens means taking ten away from the previous number in the sequence. Try it: 100, 90, ….., ….., ….., ….., Now try to complete this sequence. Can you fill in the gaps? 120, ….., 100, ……, ……, 70
Counting on and back in hundreds. Counting on and back in hundreds is similar to the tens but this time you use hundreds instead. Counting on: 100, 200, 300, 400, 500 Counting back: 500, 400, 300, 200, 100
Look carefully at this sequence! What changes in this sequence? 256, 356, 456, 556, 656, 756, 856, 956 What stays the same?
Look at these sequences. Discuss with your friend what is happening in each one. 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, , 132, 142, 152, 162, 172, , 521, 621, 721, 821, 921, 1021