Page 42 - TG_G1_CH6_CHRIS

1 There were 20 bunnies in the
field. I saw 13 more bunnies in Problem-Solving questions 1 and 2 include:
the forest. How many bunnies • Adding 2-digit number with a multiple of ten
did I see in all?
• Solving word problem concerning Addition of a 2-digit number and a
33 bunnies
multiple of ten
2 Can you tell which of the two addition sentences below will give
the larger number, without adding? Explain.
In order to reinforce children’s ability to add 2-digit numbers with a multiple of
ten in a real-life situation, have them solve problem 1. Encourage them to read
First: 47 + 2 = Second: 47 + 20 =
the situation carefully and guide them to use the place value chart to find the
Yes. 20 is 10 times more than 2, so 47 + 20 will have sum of bunnies in the field. The answer is 33 bunnies.
greater sum than 47 + 2.
Then have children explore a situation that includes making an inference and
justifying the answer in their own words in problem 2. Encourage children to
Vocabulary Check Circle True or False. read the problem carefully. Guide them to use mental strategies to find each
sum such as counting on using the number line or the place value concept. Let
34 is a multiple of 10. True False them discover that when adding ones to the number the sum will be less than
when adding tens to the same number.
56 is a 2-digit number. True False
After solving exercises 1 and 2, copy the additional problems below onto the
board for group or individual work.
292
The additional problems are based on adding 2-digit numbers with a multiple
of ten. In problems 1 and 2, encourage children to use mental strategies to find
Vocabulary Check each sum. Have them use the place value chart to find the sum.

If children struggle to answer correctly, review If children have difficulty, give them a place value chart and guide
2-digit numbers and multiples of ten in Time to them to add multiple of ten to a 2-digit numbers to solve the problems.
Learn.
Additional problem 1
Melinda’s mother is 40 years old. How old will she be in 15 years?
We can use the place value chart to add multiple of tens to a two-digit
number. The answer will be 40 + 15 = 55.
EXIT ACTIVITY
Additional problem 2
In a zoo, there are 50 birds and 16 more. How many birds are there in all?
Use the Exit Activity for this lesson to We can use the place value chart to add multiple of ten to a two-digit
reinforce children’s understanding. This number. The answer will be 50 + 16 = 66 birds.
can be used as an informal formative
assessment.

CLOSURE

To make sure children understand the main concepts of the lesson, ask them to explain how to add 35 + 10.

Children can use the place value chart to add tens to a two-digit number. Tens Ones
We add tens to tens and ones to ones.
3 5
The place value chart shows the answer. + 1 0
4 5

433
433