Reasonable VS Unreasonable
Wyatt spends $47 dollars on dinner for his family. His mom said that he spend about $50. Is this reasonable?
Yes! 47 rounded to the nearest 10 is 50!
True or False: The identity property states that any number plus 0 equals that number?
Example: 9+0=9
True! Any number plus zero will always equal that number.
Round 58 to the nearest 10.
60
Round to the nearest hundred.
579
600
Jullius has 68 baby cheetahs for sale. He sells 32 of them. How many baby cheetahs does Jullius have left?
36 cheetahs for sale.
Bentley rides his bike 15 miles to school. After school, Bentley rides his bike 12 more miles to the movies. After his movie, Bentley has to ride his bike 22 miles home. His mom said that he had almost rode his bike 50 miles that day! Is this reasonable or unreasonable?
Reasonable!
15+12= 27
27+22= 49
49 rounded to the nearest 10 is 50!
True or False: 7+3+5 will have the same sum as 3+5+7?
True. The commutative property states that the order of addends can change and the sum will remain the same.
Round 12 to the nearest 10?
10
Round to the nearest hundred.
210
200
Athena has 13 cats and 9 dogs. Athena then adopts 2 more hamsters. How many pets does she have in total?
13+9+2=?
22+2= 24
24 pets
Weston spends 30 minutes at the store before wrestling practice. He then spends 15 more minutes eating his snack. His brother complains that Weston has taken 1 hour and 30 minutes to get ready for practice. Is this reasonable or unreasonable?
Unreasonable! It will take Weston about 45 minutes to get ready for practice.
If 6+11+4= 21 then what would 4+11+6=?
21
The commutative property states that the order of addends does not matter and the sum will be the same.
True or False?
187 rounded to the nearest 10 would be 200?
False!
187 rounded to the nearest hundred would be 200.
187 rounded to the nearest 10 would equal 190.
True or False: 120 rounded to the nearest hundred is 200.
False!
120 rounded to the nearest hundred would be 100. 0-4 slide to the floor!!!!
Kennedy draws 36 pictures. She then paints 5 more. Kennedy decides to sell 10 pieces of art. How many art pieces would she have left?
31 pieces of art
36+5=41
41-10=31
Lexi goes to the movies and spends $37 dollars on her ticket. She also spends $97 dollars on snacks. Lexi says she spend about $100. Is this reasonable or unreasonable?
Unreasonable!
It cost Lexi almost 100 dollars just for her snacks! If she had to pay for her ticket and her snacks, she would need much more than 100 dollars.
$37+$97= 134
What do parenthesis in a math equation tell us to do?
Example: (5+3)+2
The parenthesis tell us what to do first in our equation.
Example: (5+3)+2=10
Round to the nearest 10:
166
122
170
120
True or False: 361 rounded to the nearest hundred is 400.
True! 5-9 climb up the vine
Jersey collected 60 coins. Gabby collected 15 crystals. Maddie collected 5 pairs of earrings. If the girls wanted to combine their collection, how many things would they have in total?
80 things!
60+15+5=80
About 500 horses live on Ahrora's farm. If the actual number of horses was round to the nearest hundred, how many horses might be at Ahrora's farm?
a. 579
b. 409
c. 448
d. 511
511 rounded to the nearest hundred is 500!
Solve the equation:
(20-4)+6=
22
20-4=16
16+6=22
Round to the nearest 10:
239
11
84
240
10
80
Round to the nearest hundred:
102
330
238
100
300
200
Chase caught 130 fish while he was ice fishing. Kingston caught 45 fish. After a while of fishing, Chase got hungry and ate 27 pieces of fish. How many fish do the boys have left?
148 fish left!
130+45= 175
175-27= 148