Subject

Mathematics

Class

ICSE Class 10

Pre Boards

Practice to excel and get familiar with the paper pattern and the type of questions. Check you answers with answer keys provided.

Sample Papers

Download the PDF Sample Papers Free for off line practice and view the Solutions online.
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 Multiple Choice QuestionsLong Answer Type

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31.

The 4th term of an A.P. is 22 and 15th term is 66. Find the first term and the common difference. Hence find the sum of the series to 8 terms.


Let  'a'  be the first term and  'd'  be the common difference of given  A.P.

Now,

4th term = 22

 a + 3 d = 22        ............( i )

 

15th term = 66

 a + 14 d = 66      ............( ii )

 

Subtracting  ( i )  from  ( ii ),  we have

11 d = 44

 d = 4

Substituting the value of  'd'  in  ( i ),  we get

a = 22 - 3 x 4 

   = 22 - 12

   = 10

 First term = 10.

Now,

Sum of  n  terms = n2  2 a + ( n - 1 ) d 

Sum of  8  terms = 82  2 × 10 + ( 8 - 1 ) × 4                                  = 82  2 × 10 + 7 × 4                            = 4  20 + 28                            = 4 × 48                           = 192


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32.

Use Graph paper for this question.  A survey regarding height (in cm) of 60 boys belonging to Class 10 of a school was conducted. The following data was recorded:

 

Height in cm 135 - 140 140 - 145 145 - 150 150 - 155 155 - 160 160 - 165 165 - 170
No. of boys 4 8 20 14 7 6 1

 

Taking 2 cm = height of 10 cm along one axis and 2 cm = 10 boys along the other
axis draw an ogive of the above distribution. Use the graph to estimate the following:

(i) the median

(ii) lower Quartile

(iii) if above 158 cm is considered as the tall boys of the class. Find the number of
boys in the class who are tall.


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