Last week we looked and number bonds to 20. This week we will be looking at these again as well as looking at number facts! (Please have a read of the page linked above for more information on teaching number facts.)
Can you use the rainbow to help you fill in the number bonds to 20 facts?
If you think you already know them, you can do this without using the rainbow! I'll help you with the first one which is a brown colour. If I start on 0 and follow the brown arch of the rainbow, I get to 20!
That means that 0 + 20 = 20. Next door is another brown sum to fill in. We can use number facts to help us with this one. We know the 0 + 20 = 20 so if we swap the numbers we are adding around, it makes a new sum with the same answer! 20 + 0 = 20. Remember when we add numbers, it doesn't matter which one we start with, we will always end up with the same answer. Check your answers using blocks or the rainbow to make sure you have the right answers. If you have a go on your own and make a mistake, don't worry because in school we don't mind mistakes as they help us learn. You could even use a green pen or pencil to go over your work with an adult or older family member at home. Any wrong answers could be worked out together and written next to your original answer.
Don't feel like you have to print any of the worksheets attached, you can do your own version outdoors or on plain paper - whatever works best for you!
Can you solve the following problems using your number bonds to 20?
If you can't remember them, count on until you get to 20 using blocks/ beads/ pasta, etc.
If you find this difficult, see if you can use the number bonds to 20 sheet attached.
Remember to write the units your answer is and show your workings! e.g. 14 + 6 = 20 strawberries.
1) 20 children are going to Jump Jam for a party. 16 of them brought their own socks. How many children didn't bring socks?
( _____ children didn't bring socks.)
2) Dosbarth Garw went on a school trip. When they were on their way they saw 15 yellow cars on the way and only 5 on the way home. How many yellow cars did they see altogether?
( Dosbarth Garw saw _____ yellow cars on their trip.)
3) Arwen and Ruby were playing a game of Snap. Arwen had 9 cards and Ruby had 11 cards. How many cards did they have altogether?
(There are ____ cards altogether.)
4) William, Tomos and Spencer were doing their Daily Mile, on the yard. Miss Rowley said the class had to do 20 laps around the whole yard. They ran 14 laps very quickly. How many more laps have they got to run?
(They need to run ____ more laps.)
5) Ellie was drawing a picture of a fierce crocodile in a tutu. She wanted him to have 20 spikes. She started drawing but only put 18 on his back. How many more does she need to draw?
(Ellie should draw ____ more spikes on the crocodile's back)