Wired Faculty-
Call Us
+91 8076753736 -
Send us an Email
[email protected]
Direct And Inverse Proportions
Question
A school has 9 periods a day each of 50 minutes duration. How many period will there be. if the duration of every period is reduced by 5 minutes?
Solution
Presents duration each period = (50 - 5) minutes = 45 minutes.
Let the present number of period be ‘x’.
Since, more the number of periods, less is the duration of a period.
∴ It is a case of inverse variation.
We have:
|
Number of periods |
Diuration of each period (in minutes) |
|
9 |
50 |
|
X |
45 |
Sponsor Area
Some More Questions From Direct and Inverse Proportions Chapter
A photograph of a bacteria enlarged 50,000 times attains a length of 5 cm as shown in the diagram. What is the actual length of the bacteria? If the photograph is enlarged 20,000 times only, what would be its enlarged length?
In a model of a ship, the mast is 9 cm high, while the mast of the actual ship is 12 m high. If the length of the ship is 28m, how long is the model ship?
Suppose 2 kg of sugar contains 9 x 106 crystals. How many sugar crystals are there in (i) 5 kg of sugar? and (ii) 1.2 kg of sugar?
Rashmi has a road map with a scale of 1 cm representing 18 km. She drives on a road for 72 km. What would be her distance covered in the map?
A 5 m 60 cm high vertical pole casts a shadow 3 m 20 cm long. Find at the same time (i) the length of the shadow cast by another pole 10 m 50 cm high and (ii) the height of a pole which casts a shadow 5 m long.
A loaded truck travels 14 km in 25 minutes. If the speed remains the same, how far can it travel in 5 hours?
On a squared paper, draw five squares of different sides. Write the following information in a tabular form.
|
Square 1 |
Square 2 |
Square 3 |
Square 4 |
Square 5 |
|
|
Length of a side (L) |
|||||
|
Perimeter (P) |
|||||
|
L/P |
|||||
|
L/A |
Find whether the length of a side is in direct proportion to:
(a) The perimeter of the square.
(b) The area of the square.
Question: Observe the following tables and find which pair of variables (here x and y) are in inverse proportion.
(i)
|
X |
50 |
40 |
30 |
20 |
|
y |
5 |
6 |
7 |
8 |
(ii)
|
X |
100 |
200 |
300 |
400 |
|
y |
60 |
30 |
20 |
15 |
(iii)
|
X |
90 |
60 |
45 |
30 |
20 |
5 |
|
y |
10 |
15 |
20 |
25 |
30 |
35 |
1. Which of the following are in inverse proportion?
(i) The number of workers on a job and the time to complete the job.
(ii) The time taken for a journey and the distance travelled in a uniform speed.
(iii) Area of cultivated land and the crop harvested.
(iv) The time taken for a fixed journey and the speed of the vehicle.
(v) The population of a country and the area of land per person.
In a television game show, the prize money of Rs 1,00,000 is to be divided equally amongst the winners. Complete the following table and find whether the prize money given to an individual winner is directly or inversely proportional to the number of winners?
|
Number of winners |
1 |
2 |
4 |
5 |
8 |
10 |
20 |
|
Prize for each winner (in Rs) |
1,00,000 |
50,000 |
... |
... |
... |
... |
... |
Mock Test Series
Sponsor Area