Ostukorv on tühi
MULTIPLICATION IN WORDS
How many hats are there on the heads
of all the dragons?
7 + 7 + 7 =
If all the factors of an addition are the
same number, we can use multiplication.
3 \latex{ \times} 7 =
=
There are
hats on the dragons.
The names of all the factors in the multiplication:
3 \latex{ \times} 7 = 21
factors
product
{{exercise_number}}. Fill in the missing numbers.
2·7=
9·4=
8·6=
7·7=
5·6=
3·8=
4·
5·
9·
·3=18
·4=28
·2=16
=24
=15
=18
{{exercise_number}}. Write it down with an operation, then finish the calculation.
The product of 6 and 7:
Six time more than 5:
Four times seven:
Seven times 9:
Eight times 3:
One times 8:
Zero times 3:
Nine times ten:
∙
∙
∙
∙
∙
∙
∙
∙
{{exercise_number}}. Calculate the products
17·8=10·8+7·8=
+
=
13·6=
32·4=
25·3=
46·7=
28·9=
26·5=
19·4=
a)
b)
{{exercise_number}}. Which one is more? Use the right (<,>,=) relational sign.
12·4
10·5
23·4
24·3
34·3
13·7
9·11
2·43
24·5
23·6
15·2
12·5
How many cookies are there on the table?
If we switch the factors of a product, the product does not change.
Bob sees 6 rows
with 4 cookies in
each row.
6 \latex{ \times} 4 =
They both see
cookies.
6 \latex{ \times} 4 = 4 \latex{\times } 6
Gabe sees 4 rows
with 6 cookies in
each row.
4 \latex{ \times} 6 =
{{exercise_number}}. Fill in the missing numbers.
6·8=8·
3·9=9·
4·7=7·
9·34=
25·6=
17·3=
10·
3·
·1=1·30
=20·3
=6·10
·17
·25
·9
{{exercise_number}}.
An office bought 3 boxes of CD-s.
There were 6 packs in each box,
with 5 CD-s in each pack.
How many CD-s did the office buy?
We can count this way:
One box contains 6 \latex{\times } 5 CD-s,
3 such boxes contains
3 \latex{ \times} (6 \latex{\times } 5) =
3 \latex{ \times} 30 =
= 90;
or this way:
3 boxes contain 3 \latex{\times } 6 pack, with 5 CD-s in each pack,
altogether (3 \latex{ \times} 6) \latex{\times } 5 =
18 \latex{\times } 5 =
= 90
3 \latex{ \times} (6 \latex{\times } 5) = (3 \latex{ \times} 6) \latex{\times } 5.
In case of a multi factor product, the product does not change if we group the factors differently.
{{exercise_number}}. Calculate in a clever way.
7·(5·4)=7·20=
5·20·9=
9·6·5=
3·15·4=
4·25·5=
3·5·8=
{{exercise_number}}. How much is it worth?
7 \latex{ \times}
7 \latex{ \times}
7 \latex{ \times}
7 \latex{ \times}
1 ¢ =
10 ¢ =
100 ¢ =
€1,000 =
€
¢
¢
¢
{{exercise_number}}.
a) Write all the two digit numbers where the tens digit is two less than the units digit
in the first row of the table.
b) Write down ten times
and a hundred times
the numbers.
Observe, how the
product changes.
13·10=
13·100=
24· 10=
24·100=
13
130
1300
24
\latex{ \times}10
\latex{ \times}100
\latex{ \div}10
\latex{ \div}100
\latex{ \times}10
\latex{ \times}100
\latex{ \div}10
\latex{ \div}100
If one of the factors is multiplied by a number - the other factor is unchanged -,then the product is also multiplied by that number.
If one of the factors is divided by a number - the other factor is unchanged -,than the product is also divided by that number.
If one of the factors is divided by a number - the other factor is unchanged -,than the product is also divided by that number.
{{exercise_number}}.
a) Complete the calculations.
If a number times ten is 750, then times a hundred is
10·
=750
100·
=
If a number times ten is 90, one thousand times is
If a number times a hundred is 2,800, ten times is
If a number times one thousand is 7,000, one hundred times is
b) What numbers could the letters stand for?
46 \latex{ \times } A = 460
46 \latex{ \times } B = 4,600
A=
B=
D=
C=
37 \latex{ \times } D = 3,737
37 \latex{ \times } C = 3,700
{{exercise_number}}. Complete the calculations.
4 \latex{ \times } 200 =
4 \latex{ \times } 2,000 =
2,000 \latex{ \times } 5 =
200 \latex{ \times } 5 =
3 \latex{ \times } 300 =
3 \latex{ \times } 3,000 =
{{exercise_number}}. Fill in the missing numbers.
7
9
4
5
6
3
\latex{ \times }8
\latex{ \times }100
\latex{ \times }800
\latex{ \times }300
\latex{ \times }3000
\latex{ \times }1000
\latex{ \times }100
\latex{ \times }100
\latex{ \times }9
\latex{ \times }4
\latex{ \times }2
\latex{ \times }
\latex{ \times }
\latex{ \times }
\latex{ \times }
\latex{ \times }
\latex{ \times }
\latex{ \times }
a)
b)
{{exercise_number}}. Fill out the tables.
\latex{ \times }
\latex{ \times }
20
200
40
400
3
1
9
7
4
8
5
300
700
0
150
560
{{exercise_number}}. Solve the multiplications.
48 \latex{ \times } 2 =
48 \latex{ \times } 20 =
48 \latex{ \times } 200 =
23 \latex{ \times } 400 =
23 \latex{ \times } 40 =
23 \latex{ \times } 4 =
17 \latex{ \times } 3 =
17 \latex{ \times } 30 =
17 \latex{ \times } 300 =
{{exercise_number}}. Calculate according to the sample.
6 times a number is 246. What is it 60 times?
5 times a number is 715. What is it 50 times?
300 times a number is 7,200. What is it 3 times?
40 times a number is 3,280. What is it 4 times?
∙
∙
∙
∙
6·
=246
60·
=
{{exercise_number}}. Complete the calculations, by breaking up the factors as shown in the samples.
4 \latex{ \times } 56; 270 \latex{ \times } 3; 2,007 \latex{ \times } 3; 380 \latex{ \times } 4; 510 \latex{ \times } 7; 180 \latex{ \times } 3; 5 \latex{ \times } 490; 4 \latex{ \times } 2,030
207 \latex{ \times } 3 = 200 \latex{ \times } 3 + 7 \latex{ \times } 3 = 600 + 21 = 621
4 \latex{ \times } 506 = 4 \latex{ \times } 500 + 4 \latex{ \times } 6 =
4 \latex{ \times } 560 = 4 \latex{ \times } 500 + 4 \latex{ \times } 6 =
+
+
=
=
{{exercise_number}}. Complete the calculations.
63 \latex{ \times } 40 =
58 \latex{ \times } 60 =
290 \latex{ \times } 20 =
170 \latex{ \times } 30 =
63·4·10=
·10=
200·20+90·20=
+
=
a)
b)
c)
13 \latex{ \times } 50
17 \latex{ \times } 40
26 \latex{ \times } 30
240 \latex{ \times } 20
180 \latex{ \times } 50
310 \latex{ \times } 30
{{exercise_number}}.
- 140 plants are planted in one row. How many plants are there in 30 rows?
- A box of ice cream is 500 g. How much do 15 boxes weigh?
- One salami weighs 1,200 g. How much do 3 salamis weigh?
{{exercise_number}}. Follow the sample, and do the calculations simply.
a)
b)
17 \latex{ \times } 6 + 17 \latex{ \times } 4 = 17 \latex{ \times } (6 + 4) = 17 \latex{ \times } 10 = 170
9 \latex{ \times } 150 = 10\latex{ \times }150\latex{ - }1\latex{ \times }150 = 1500\latex{ - }150 = 1350
62 \latex{ \times } 15 + 62 \latex{ \times } 85 =
128 \latex{ \times } 3 + 128 \latex{ \times } 7 =
46 \latex{ \times } 89 + 54 \latex{ \times } 89 =
450 \latex{ \times } 7 + 550 \latex{ \times } 7 =
9 \latex{ \times } 410=
99 \latex{ \times } 53=
4 \latex{ \times } 748=
5 \latex{ \times } 249=
{{exercise_number}}. Fill in the missing numbers. Compare the products.
12·4=
200·9=
150·7=
·
·
·
=
=
\latex{ \times }2
\latex{ \times }10
\latex{ \times }3
\latex{ \div }3
\latex{ \div }10
\latex{ \div }2
The product is unchanged if one of the factors is multiplied by a number, while the the other factor is divided by the same number.
{{exercise_number}}. Fill in the numbers to make the statements true. Complete the calculations.
=
=
=
=
=
=
=
=
74 \latex{ \times } 20 = 74 \latex{ \times }2\latex{ \times }
39 \latex{ \times } 100 = 390 \latex{ \times }
71 \latex{ \times } 100 =
87 \latex{ \times } 100 =
\latex{ \times } 10
\latex{ \times } 10
76 \latex{ \times } 100 = 760 \latex{ \times }
83 \latex{ \times } 50 = 83 \latex{ \times }5\latex{ \times }
64 \latex{ \times } 30 = 64 \latex{ \times }3\latex{ \times }
97 \latex{ \times } 40 = 97 \latex{ \times }4\latex{ \times }
{{exercise_number}}.
At the shop they wrote down, how many of each drink they sold. How much was
the daily sale of each drink? Fill out the table.
soft drink
juice
tea
water
amount
sold
income
¢
db
db
db
db
¢
¢
¢
PRICES
soft drink
juice
tea
45 ¢
53 ¢
23 ¢
water
30 ¢
{{exercise_number}}. Which one is more? Use the right relational sign.
3,700 \latex{ \times } 2
460 \latex{ \times } 5
230 \latex{ \times } 10
370 \latex{ \times } 20
(570\latex{ - }230) \latex{ \times } 5
410 \latex{ \times } 2 + 160 \latex{ \times }4
490 \latex{ \times } 2
570 \latex{ \times } 5 \latex{ - } 230
{{exercise_number}}.
A package of cookies is 120 ¢. If you spend over 2,500 ¢ you get a discount of 250 ¢.
Fill out the table with the help of the flow diagram.
package
package · 120 ¢
Does
the value exceed
2,500 ¢?
amount
to be paid
250 ¢
yes
no
when buying 30 bags:
30 \latex{ \times }120 ¢= 3,600 ¢.
3,600 ¢ > 2,500 ¢, you get the discount
3,600 ¢ \latex{ - } 250 ¢ =
package
value
amount
(¢)
(¢)
(
)
¢
30
20
25
9
10
40
22
7,200
How many bags of cookies can we buy for 2,500 ¢?
{{exercise_number}}. Calculate two and three times the values rounded to hundreds.
1,578 \latex{ \approx } 1,600
1,600 \latex{ \times } 2 = 1,000 \latex{ \times } 2 + 600 \latex{ \times } 2 = 2,000 + 1,200 = 3,200
1,600 \latex{ \times } 3 = 1,000 \latex{ \times } 3 + 600 \latex{ \times } 3 = 3,000 + 1,800 = 4,800
948
1,219
2,841
2,063
3,104
1,628
{{exercise_number}}. Put the products in increasing order, read their letters together.
S
A
N
O
W
M
N
1,300 \latex{ \times } 2
2,100 \latex{ \times } 3
1,000 \latex{ \times } 4
990 \latex{ \times } 5
1,700 \latex{ \times } 3
1,100 \latex{ \times } 5
4,700 \latex{ \times } 2
Solution:
