# CLASS-8PROBLEM & SOLUTION OF ROUNDING OFF

PROBLEM & SOLUTION OF ROUNDING OFF

Example.1) Convert 0.0135428 to two significant figures and two decimal places

Answer) As per the given condition, we have to find out the round-off figure of the number 0.0135428 to two decimal places.

So,   0.0135428 = 0.013, rounded off to two significant figures

=  0.01, rounded of two decimal places

So, the desired number is 0.01        (Ans.)

Example.2) Convert 23.457812 to three significant figures

Answer)  As per the given condition, we have to find out the round-off figure of the number 23.457812 to three decimal places.

So, 23.457812

=  23.4578, rounded off  to three significant figures

=  23.458, rounded off to three decimal places

So, the desired number is 23.458      (Ans.

Example.3) Convert 124.354579 to four significant figures

Answer) As per the given condition, we have to find out the round-off figure of the number 124.354579 to four decimal places.

124.354579 = 124.35457, rounded off to four decimal figures.

=  124.3546, rounded off to four decimal places.    (Ans.)

Example.4) Convert \$ 68654 to the nearest \$ 10,000

Answer)  As per the given condition, we have to find out the round-off figure of the number \$ 68654 to nearest or closer form to \$ 10,000.

\$ 68654 is nearest or closer to \$ 68700 than \$ 68600

So, \$ 68654 = \$ 68700, to the nearest \$ 10,000   (Ans.)

Example.5) Convert 12.7534 kg to the nearest gm

Answer)  as per the given condition, if we convert Kg to gm then we will find 12.7534 Kg = 12753.4 gm which is closer to 12753 gm ( which is 12.753 Kg) than to 12754 gm      (Ans.)

Example.6)  Convert 75.12 m to cm

Answer) as per the given condition, if we convert m to cm then we will find  75.12 m = 7512 cm which is closer to 7500 cm ( which is 75 m ) than to 7600.

So, the desired result is 7500 cm or 75 m to the nearest cm.   (Ans.)

Example.7)  Express 3 / 253 as decimal number correct to a) three decimal places, b) three significant figures

3 )  253 ( 84.3333

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a)  3 / 253 = 84.333, correct to three decimal places ( as 3 is the fourth decimal place 3 < 5 )         (Ans.)

b)  3 / 253 = 84.333, correct to three significant figures ( as 3 is the fourth significant digit and 3 < 5 )      (Ans.)