Speed of a speed-boat when moving in the direction parallel to the direction of the current is 16 km/hr. Speed of the current is 3 km/hr. So the speed of the boat against the current will be (in km/hr)

A man can row 6 km/hr. in still water. It takes him twice as long to row up as to row down the river. Find the rate of stream

A boat covers 1200 km distance whose downstream speed is y kmph and the speed of the boat upstream is 60% of the speed of the boat downstream. If the difference between the time taken by the boat upstream and downstream is 32 hours. Find the distance covered by the boat in 5 hours if they traveled with the speed of still water.

The total time by the boat to cover 72 km upstream and 180 km downstream in 16 hours. The total time taken by the same boat to cover 108 km upstream and 126 downstream in 16 hours. If the sum of the upstream speed and downstream speed of the boat is 30 km, then find the speed of the stream.

The time taken by the boat can travel 240 km distance along the stream is equal to the time taken by the boat can travel 144 km distance against the stream. The speed of the boat is 20 km/hr. Find the speed of the stream.

A boat takes 26 hours for travelling downstream from point A to point B and coming back to point C midway between A and B. If the velocity of the stream is 4 km/hr and the speed of the boat in still water is 10 km/hr, what is the distance between A and B?

Speed of a boat in standing water is 12 kmph and the speed of the stream is 3 kmph. A man rows to a place at a distance of 6300 km and comes back to the starting point. The total time taken by him is:

A man rows to a place 60 km distant and come back in 35 hours. He finds that he can row 4 km with the stream in the same time as 3 km against the stream. Find the speed in still water and in stream:

A man can row 40 kmph in still water and the river is running at 10 kmph. If the man takes 2 hr to row to a place and back, how far is the place?

The speed of a boat in still water is 15 km/hr. It can go 30 km upstream and return downstream to the original point in 4 hrs 30 min. The speed of the stream is:

A boatman goes 4 km against the current of the stream in 1 hour and goes 2 km along the current in 10 minutes. How long will it take to go 24 km in stationary water?

If sum of upstream and downstream speed of a boat is 82 kmph, and the boat travels 105 km. upstream in 3 hr, Find the time taken by boat to cover 141 km downstream.

The variance of 6 values is 64. If each value is doubled, find the standard deviation.

Find the range of 11, 22, 6, 2, 4, 18, 20, 3.

Find the mode of 1,2,3,5,4,8,7,5,1,2,5,9,15 ?

Find the mean of the prime numbers between 9 and 50?

What is the difference between the mean and median of set S = {2, 4, 6, 7, 7, 13, 18, 92}?.

What is the difference between the median and mode of S={1, 2, 4, 4, 8, 14, 32, 64}?.

What is the relation among mean, median & mode ?.

If the mean of 5 observations x +1,x + 2, x + 3 , x + 4 and x + 5 is 15 then what is the mean of the first 3 observations?

The mean deviation about mean of the values 18, 12, 15 is :

The average of a set of 30 numbers is 25. If three numbers 13, 15 and 20 are discarded, then the average of the remaining numbers is

The measure of dispersion which uses only two observations is called:

Any measure indicating the centre of a set of data, arranged in an increasing or decreasing order of magnitude, is called a measure of:

The sum of the squares of the deviations of the values of a variable is least when the deviations are measured from:

The sum of deviations taken from mean is:

The frequency distribution of diameter (D) of 101 steel balls is given in the following list-

D(mm)	43	44	45	46	47	48
No.	13	15	22	21	16	14

find the mean of the diameter in mm

If the value of mean and mode of a grouped data are 50.25 and 22.5 respectively, then by using the empirical relation, find the median for the grouped data.

If the mean of the following frequency distribution is 8. Find the value of p.

x	2	4	6	p+6	10
f	3	2	3	3	2

Study the following graph and answer the question given below. The below Histogram shows the data of the annual rainfall (in cm).

Find the difference in the number of times the rainfall above 130 cm and the number of times the annual rainfall below 130 cm.

Study the following graph and answer the question given below. The below Histogram shows the data of the annual rainfall (in cm).

The number of times annual rainfall below 120 cm is what percent of the number of times the annual rainfall above 130 cm?

Study the following graph and answer the question given below.

What percentage (approx.) of the employees working in the range of Rs. 30,000 - Rs. 40,000?

If the median and the mode of a set of data are 12 and 15, respectively, then find the value of thrice the mean of the same data set.

If A, B and C are denoting Mean, Median and Mode of a data and A ∶ B = 9 ∶ 8 then the ratio of B ∶ C is:

Find the mean deviation about the mean of the distribution:

Size	20	21	22	23	24
Frequency	6	4	5	1	4

The standard deviation of the data 6, 5, 9, 13, 12, 8, 10 is

The variance of 6, 8, 10, 12, 14, 16 is:

A histogram is to be drawn for the following frequency distribution

Class Interval	5-10	10-15	15-25	25-45	45-75
Frequency	6	12	10	8	15

The adjusted frequency for class interval 15 - 25 will be :

Find the range and the coefficient of the range of the following data:

Marks 20 - 30, 30 - 40, 40 - 50, 50 - 60, 60 - 70, 70 - 80, 80 - 90

No. of Students = 10, 12, 15, 20, 25, 13, 38

What is the mean of data given in table?

Value (X)	Frequency (Y)
6	25
3	30
5	40
2	35
4	12
6	26

Calculate the mean of the following table:

Interval	f_i
0-10	6
10-20	5
20-30	7
30-40	8
40-50	3

The mean of the observations 29, x + 1, 33, 44, x + 3, x + 6 and 46 is 39. Then, the median of the observations is :

The median of the observations 11, 12, 14, 18, x + 2, 22, 22, 25 and 61, arranged in ascending order, is 21. Then, value of 3x + 7 is:

Following table shows marks obtained by 40 students. What is the mode of this data ?

Marks obtained	42	36	30	45	50
No. of students	7	10	13	8	2

The mean of 10 observations was calculated as 40. It was detected on rechecking that the value of one observation 45 was wrongly copied as 15. Find the correct mean.

What is the sum of mean, mode and median of the following data?

14, 9, 12, 11, 15, 28, 23, 17, 28, 53 ?

If (a + b + c) = 17, and (a²+ b² + c²) = 101, find the value of (a - b)² + (b - c)² + (c - a)².

If $(4y-\frac{4}{y})=11$ , find the value of $(y^2+\frac{1}{y^2})$ .

If $x-\frac{1}{x} = 3$ , then the value of $x^3-\frac{1}{x^3}$ is

f (a + b + c) = 12, and (a²+ b² + c²) = 50, find the value of (a³ + b³ + c³ - 3abc)

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