Problems like 37 79 I

Зарегистрируйтесь, чтобы просмотреть полный документ!

Problems like 37 + … = 79 I am learning to add mentally the ones and tens separately when appropriate. 84 Tens Ones

Sam has $36 and is saving to buy a scooter for $78. How much more must he save? Step 1: Let’s record what he needs. $70 (seven $10) $8 (eight $1) Step 2: Now record how much he actually has. $30 (three $10) $6 (six $1) Step 3: You can now see how much he must save. Four $10 notes or $40 and two $1 coins or $2 $40 + $2 = $42 Sam must save $42 Important: Notice how both the ones and tens amount Sam has are both less than the amount he needs. This strategy works for problems like this.

Kate has $14 and is saving to buy a concert ticket for $48. How much must she save? Step 1: Let’s record what she needs. $40 (four $10) $8 (eight $1) Step 2: Now record how much she actually has. $10 (one $10) $4 (four $1) Step 3: You can now see how much she must save. Three $10 notes or $30 and four $1 coins or $4 $30 + $4 = $34. Kate must save $34 Important: Notice how both the ones and tens amount Kate has are both less than the amount she needs. This strategy works for problems like this.

Taine has $35 and is saving to buy a new watch for $89. How much must he save? Try doing this example in your head. Step 1: How many $1 coins must he save. 4 ($4) Step 2: How many $10 notes must he save. 5 ($50) Step 3: Add the two amounts together. How much must he save? $50 + $4 = $54

Now try these questions on your own. Remember to add the ones and tens separately. 1) 34 + …. = 76 40 + 2 = 42 2) 18 + …. = 59 40 + 1 = 41 3) 63 + … = 88 20 + 5 = 25 4) 12 + …. = 65 50 + 3 = 53 5) 36 + …. =87 Click again when you have completed each question and the answer will be displayed. 50 + 1 = 51 Need some more practise? Try Pg 48 of Teacher Tools Addition and Subtraction Book Numeracy resources

Скачать презентацию Problems like 37 79 I

bc1fb4f04c78ac1cd4fa71872384ae81.ppt

Количество слайдов: 5