Page 298 - Start Up Mathematics_7

let’s evaluate
1. Find the median of the first:
(a) hundred whole numbers (b) hundred natural numbers (c) twenty-five odd numbers

2. The average age of a group of 7 athletes is 22 years. An athlete whose age is 36 years joins
the group. Will the average age of the group increase or decrease? Find out by how much?
3. The average of 3 different numbers is 17. Two of the numbers are 8 and 12. Find the third
number.
4. Name the measure of central tendency associated with each phrase.
(a) middle (b) most often (c) average
5. List the natural numbers whose measure of central tendencies is as under:
mean = median = mode = 4. Is the answer unique?

Thinking Skills

1. The following table represents the distance travelled by different vehicles using 1 litre of
various types of fuel.

Type of vehicle Ordinary petrol Premium petrol Diesel
Car 13 km 15 km 17 km
Bus 5 km 7 km 6 km
3 wheeler 10 km 12 km 10 km

(a) Find the average distance covered by the car in 1 litre of fuel?
(b) What is the average distance travelled by the vehicles using diesel as fuel?

2. The blood pressure of patients coming to a Government hospital are as under:
160, 130, 142, 150, 135, 190, 142, 160, 142, 174, 142, 158, 150, 160, 142, 142, 130, 158,
160, 174
For the above data, evaluate the: (a) mean (b) median (c) mode
3. An elevator has a capacity of 401 kg. A total of 9 people enter it at the ground floor. There
weights in kg are tabulated below:

A B C D E F G H I
60 20 88 42 73 20 98 13 91

(a) Find the total weight of 9 persons?
(b) Find the arithmetic mean.
(c) If the lift should carry maximum number of persons, who should exit?
(d) Find the maximum number of persons who should exit for the elevator to work.

(e) If the lift should carry maximum weight, who should exit?
4. The following table shows the points scored out of 10 by each player in 4 trials:

Player Trial 1 Trial 2 Trial 3 Trial 4
Sujoy 8.6 9 7 9
Devika 9 0 8 7
Jessica 9.3 8.3 9 Did not play

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