Grouped Frequency Distribution | Statistics | Assessment | English | Grade 9

The class mark of the class 250 - 280 is ______

• 255

• 260

• 265

• 270

Answer explanation

Class mark = (Lower limit + Upper limit)/2 = (250 + 280)/2 = 265

Tags

CCSS.7.SP.B.4

The marks obtained by 10 students in a Mathematics test(out of 100) are given below. 48, 52, 62, 68, 72, 75, 100, 92, 38, 84 Determine the range of the marks.

• 62

• 68

• 60

• 72

Answer explanation

Range = Highest marks - Lowest marks = 100 - 38 = 62

Tags

CCSS.6.SP.B.5

CCSS.6.SP.A.3

In a frequency distribution, the mid - value of a class is 25 and the width of the class is 20. The lower limit of the class is _____

• 25

• 15

• 10

• 20

Answer explanation

Mid - value = 25 Width = 20 Lower limit = Mid value of class - (Width/2) = 25 - (20/2) = 25 - 10 = 15

Tags

CCSS.6.SP.A.2

CCSS.6.EE.B.7

The class mark of a class is 45 and if the upper limit of that class is 60, then its lower limit is ______

• 25

• 40

• 50

• 30

Answer explanation

Upper limit = 60 Class mark = 45 Lower limit = x Now, Class mark = (Lower limit + Upper limit)/2 45 = (x + 60)/2 90 = x + 60 x = 90 - 60 x = 30

Tags

CCSS.6.EE.B.7

CCSS.6.EE.B.5

The mid - value of a class interval is 52. If the class size is 10, find the upper and lower limits of the class.

• 48 - 58

• 45 - 55

• 47 - 57

• 50 - 60

Answer explanation

Let upper limit and lower limit be x and y, (x + y) /2 = 52 ∴ x + y = 104 ......(1) Now, according to the question x - y = 10 ........(2) Adding equation (1) and (2) we get, 2x = 114 ∴ x = 57 and 57 + y = 104 y = 104 - 57 y = 47 ∴ Required Class Interval is 47 - 57.

Tags

CCSS.7.NS.A.3

Choose the correct frequency distribution table for the data on height (cm) of 20 girls using the class intervals 130 - 135, 135 - 140 and so on. The heights of the girls in cm are: 139, 138, 144, 147, 165, 142, 149, 155, 149, 141, 134, 136, 131, 146, 160, 153, 133, 148, 140, 138

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Answer explanation

Tags

CCSS.6.SP.A.2

CCSS.6.SP.B.5

CCSS.6.SP.A.1

CCSS.6.SP.B.4

The frequency distribution of weights (in kg) of 50 persons is given. What are the class marks of all the class interval?

• 30, 40, 50, 60, 70

• 35, 45, 55, 65, 75

• 30.5, 40.5, 50.5, 60.5, 70.5

• 35.5, 45.5, 55.5, 65.5, 75.5

Answer explanation

Class mark = (Lower limit + Upper limit)/2 1) (30 + 40)/2 = 35 2) (40 + 50)/2 = 45 3) (50 + 60)/2 = 55 4) (60 + 70)/2 = 65 5) (70 + 80)/2 = 75

Choose the correct frequency distribution table for the data of annual attendance of 40 students in standard IX, using the class intervals 155 - 165, 165 - 175 and so on. Annual attendance: 171, 183, 192, 168, 156, 162, 158, 159, 178, 192, 186, 173, 169, 162, 182, 191, 194, 169, 174, 158, 186, 174, 176, 181, 179, 193, 164, 176, 159, 158, 166, 168, 187, 188, 192, 194, 166, 173, 179, 187

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Answer explanation

Tags

CCSS.6.SP.A.2

CCSS.6.SP.B.5

CCSS.6.SP.A.1

CCSS.6.SP.B.4