6. Ribbon B is 17 cm long. 10 20 15 17 17 is between 10 and 20. It is nearer to 20 than to 10. 17 is 20 when rounded off to the nearest ten. 17 is approximately equal to 20. 17 20
7. Ribbon C is 95 cm long. 90 100 95 95 95 is exactly halfway between 90 and 100. 95 is 100 when rounded off to the nearest ten. 95 100 Why numbers with 5 in the ones place is rounded off to the next tens? The number 5 is at the centre. The convention is to round off the number to the next tens.
![[object Object],[object Object],[object Object],Recall… 80 90 1 Sub-unit 1 Unit +1 +1 +1 +1 +1 +1 +1 +1 +1 +1](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)