# IGCSE Mathematics Paper-1: Specimen Questions with Answers 16 - 16 of 324

## Question 16

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### Describe in Detail

Essay▾

The table above gives the lengths of the rivers, correct to 2 significant figures.

 Rivers Length () Nile Amazon Yangtze Yellow River

(a) List the rivers in order of length, largest to smallest.

________ > ________ > Yangtze > ________.

(b) Use a whole number to complete the statement in the answer space.

The length of Amazon is approximately ________ times the length of Yellow River.

### Explanation

Here, correct the lengths of the rivers to 2 significant figures:

• Length of Nile will be: 6,900km because after second significant digit 8 there is 5, so 8 will be rounded and be 9.
• Length of Amazon will be: 7,000km because after second significant digit 9 there is 9 which is greater than 5, so 69 will be rounded and be 70.
• Length of Yangtze will be: 6,300km which has already 2 significant figures.
• Length of Yellow River will be: 5,500km because after second significant digit 4 there is 6 which is greater than 5, so 4 will be rounded and be 5.

(a) Here, list of rivers as per largest to smallest lengths as below:

Amazon > Nile > Yangtze > Yellow River

Because

(b) Here, length of Amazon by using whole number is:

Length of Yellow River by using whole number is:

So, the length of Amazon is approximately 1.2 times the length of Yellow River.

(Calculation: )