Page 24 - ICSE Math 6

4. The difference between two numbers is 8,67,593. If the smaller number is 6,34,289, find the
greater number.
5. A merchant had ` 88,592 with her. She purchased 40 video games at ` 1,200 each. How much
money was left with her after the purchase?

6. A car showroom sold 456 cars of a given model at ` 3,13,495 each. What is the total sale of the
showroom with respect to the cars of the given model?
7. A student multiplied 8,355 by 89 instead of 98. By how much was his answer less than the actual
answer?
8. A 100 m long steel wire is divided into 8 equal pieces. What is the length of each piece?

9. To stitch a trouser, 1 m 30 cm cloth is needed. Out of 15 m cloth, how many trousers can be
stitched and how much cloth will remain?
10. The distance between the school and the house of a student is 1 km 875 m. Everyday she walks
both ways. Find the total distance covered by her in 6 days.
11. A large tanker of capacity 15 kL 500 L is full of petrol. How many petrol pumps each with a
capacity of 720 L of petrol can be supplied with this tanker?

12. A man bought a piece of land for ` 5,65,49,210. He paid ` 13,45,670 for the construction materials
and ` 2,25,500 to the labours who constructed the building. How much did he spend in all?

Estimation
You might have heard statements like:

• ‘Around nine hundred people enjoyed the music concert.’
• ‘Around thirty thousand people watched the Prime Minister’s speech on YouTube.’
• ‘Around five thousand people gathered for a political meeting.’

In the above examples, the exact number of people present for the particular event is not known. It is
only a general idea about the gathering in each case.
Around nine hundred could be 876 or 908 or around thirty thousand could be 29,034 or 30,136.
If exactly 30,219 workers attended a political meeting, we can say that
about 30,000 people were present for the said meeting. If 193 teachers Maths Info
attended a workshop then, it may be said that about 200 teachers attended
the workshop. The exact number could be a little less or more than the The estimation of numbers is
number which we have stated. This process of getting a general idea of also known as rounding off
numbers.
the number is called estimation. Estimation of numbers is done to the
nearest tens, hundreds, thousands, ..., i.e., 10, 100, 1,000, and so on.

Estimation or rounding off the numbers to the nearest tens
The steps to estimate or round off a given number to the nearest tens are as follows:

Step 1: In the given number, examine the digit at ones place.
Step 2: • If the digit at ones place is less than 5, i.e., 0, 1, 2, 3, or 4, replace it by 0 and leave the
remaining digits unchanged.
• If the digit at ones place is 5 or greater than 5, i.e., 5, 6, 7, 8 or 9, replace it by 0 and
add 1 to the digit at tens place.

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