**Question 1 :**

Find the range and coefficient of range of the following data

(i) 59, 46, 30, 23, 27, 40, 52, 35, 29

(ii) 41.2, 33.7, 29.1, 34.5, 25.7, 24.8, 56.5, 12.5

**Question 2 :**

The smallest value of a collection of data is 12 and the range is 59. Find the largest value of the collection of data.

**Question 3 :**

The largest of 50 measurements is 3.84 kg. If the range is 0.46 kg, find the smallest measurement.

**Question 4 :**

The standard deviation of 20 observations is √5. If each observation is multiplied by 2, find the standard deviation and variance of the resulting observations.

**Question 5 :**

Calculate the standard deviation of the first 13 natural numbers. Solution

**Question 6 :**

Calculate the standard deviation of the following data

10, 20, 15, 8, 3, 4

**Question 7 :**

**Calculate the standard deviation of the following data.**

38, 40, 34, 31, 28, 26, 34

**Question 8 :**

Calculate the standard deviation of the following data

x 3 8 13 18 23

f 7 10 15 10 8

**Question 9 :**

The number of books bought at a book fair 200 students from a school are given in the following table.

Number of books 0 1 2 3 4

Number of students 35 64 68 18 15

calculate the standard deviation.

**Question 10 :**

The time (in seconds) taken by a group of people to walk across a pedestrian crossing is given in the table below.

Time (in sec) 5-10 10-15 15-20 20-25 25-30

No of people 4 8 15 12 11

Calculate the standard deviation.

Solution

**Question 11 :**

A group of 45 house owners contributed money towards green environment of their street. The amount of money collected is shown in the table below.

Amount 0-20 20-40 40-60 60-80 80-100

No of house 2 7 12 19 5

Calculate the standard deviation. Solution

**Question 12 :**

Calculate the variance of the following table.

x 2 4 6 8 10 12 14 16

f 4 4 5 15 8 5 4 5

**Question 13 :**

Find the variance of the following distribution

Class interval 20-24 25-29 30-34 35-39 40-44 45-49 |
Frequency 15 25 28 12 12 8 |

**Question 14 :**

The mean and standard deviation of 20 items are found to be 10 and 2 respectively. At the time of checking it was found that an item 12 was wrongly entered as 8. Calculate the correct mean and standard deviation.

**Question 15 :**

Mean of 100 items is 48 and their standard deviation is 10. Find the sum of all the items and the sum of the squares of all the items.

Apart from the stuff given on this web page, if you need any other stuff in math, please use our google custom search here.

If you have any feedback about our math content, please mail us :

**v4formath@gmail.com**

We always appreciate your feedback.

You can also visit the following web pages on different stuff in math.

**WORD PROBLEMS**

**Word problems on simple equations **

**Word problems on linear equations **

**Word problems on quadratic equations**

**Area and perimeter word problems**

**Word problems on direct variation and inverse variation **

**Word problems on comparing rates**

**Converting customary units word problems **

**Converting metric units word problems**

**Word problems on simple interest**

**Word problems on compound interest**

**Word problems on types of angles **

**Complementary and supplementary angles word problems**

**Trigonometry word problems**

**Markup and markdown word problems **

**Word problems on mixed fractrions**

**One step equation word problems**

**Linear inequalities word problems**

**Ratio and proportion word problems**

**Word problems on sets and venn diagrams**

**Pythagorean theorem word problems**

**Percent of a number word problems**

**Word problems on constant speed**

**Word problems on average speed **

**Word problems on sum of the angles of a triangle is 180 degree**

**OTHER TOPICS **

**Time, speed and distance shortcuts**

**Ratio and proportion shortcuts**

**Domain and range of rational functions**

**Domain and range of rational functions with holes**

**Graphing rational functions with holes**

**Converting repeating decimals in to fractions**

**Decimal representation of rational numbers**

**Finding square root using long division**

**L.C.M method to solve time and work problems**

**Translating the word problems in to algebraic expressions**

**Remainder when 2 power 256 is divided by 17**

**Remainder when 17 power 23 is divided by 16**

**Sum of all three digit numbers divisible by 6**

**Sum of all three digit numbers divisible by 7**

**Sum of all three digit numbers divisible by 8**

**Sum of all three digit numbers formed using 1, 3, 4**

**Sum of all three four digit numbers formed with non zero digits**