Page 74 - Start Up Mathematics_4

EXERCISE 5.9

1. Rachel has 9 packets of stickers with 125 stickers in each. How many stickers does she
have altogether?

2. Hariti and Noni join swimming classes during their summer vacations for a month. The
fees for swimming classes is ` 1,350 per person for 1 month. They give ` 3,000 to the
instructor. How much money should they get back?

3. A school has 2,146 students. There are 14 school buses. If 85 students travel in each
bus, how many students come to school by other means of transport?
4. Seema bought 3 dozen chocolates, 4 dozen packets of biscuits and 6 dozen cartons
of mango juice for her shop. If 1 chocolate costs ` 18, 1 packet of biscuit costs
` 22 and 1 carton of mango juice costs ` 325, how much did Seema pay in all?
(Hint: 1 dozen = 12)

5. Anil is a typist in a company. He types 108 pages daily. How many pages will he type
in a week?

6. Two brothers work as car mechanics in two different workshops. One earns ` 3,215
per month and the other earns ` 3,576 per month. What is their total earning in a
year?

7. 63 bags are filled with coins. There are 352 coins in each bag. How many coins are
there in all?
8. A cookie factory produced 674 packets of cookies. There were a score cookies in each
packet. How many cookies did the factory produce in all? (1 score = 20)

9. Frame two word problems for each of the following and solve them.

(a) 4,270 × 324 = ? (b) 9,123 × 35 = ? (c) 7,298 × 56 = ?
10. Simplify.

(a) 112 × 4 – 25 × 6 – 14 × 5 + 3 × 300
(b) 16 × 5 – 76 × 9 + 238 × 7 – 5 × 100

Lattice Multiplication

Let’s learn how to multiply large numbers using lattice multiplication method. It is a method
of multiplying large numbers using a grid. It is an easy method of multiplication as it breaks
the process into smaller steps.

Remember

In lattice multiplication, the numbers to be multiplied are written
outside the lattice and the products are written inside it.

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