Question

Find the square root of the following decimal numbers. 

1.  2.56 
2.  7.29 
3.  51.84 
4.  42.25 
5.  31.36

Answer 1

(i) The square root of \(2.56\) can be calculated as follows. 

	1.6
1	\(\bar2.\bar5\bar6\) \(-1\)
26	156 156
	0

∴ \(\sqrt{2.56} = 1.6\)

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(ii) The square root of \(7.29\) can be calculated as follows.

	2.7
2	\(\bar7.\bar2\bar9\) \(-4\)
47	329 329
	0

∴ \(\sqrt{7.29} = 2.7\)

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(iii) The square root of \(51.84\) can be calculated as follows.

	7.2
7	\(\bar5\bar1.\bar8\bar4\) \(-49\)
142	284 284
	0

\(\therefore\sqrt{51.84}=7.2\)

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(iv) The square root of \(42.25\) can be calculated as follows.

	6.5
6	\(\bar4\bar2.\bar2\bar5\) \(-36\)
125	625 625
	0

\(\therefore\sqrt{42.25}=6.5\)

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(v) The square root of \(31.36\) can be calculated as follows.

	5.6
5	\(\bar3\bar1.\bar3\bar6\) \(-25\)
106	636 636
	0

\(\therefore\sqrt{31.36}=5.6\)