Advertisements
Advertisements
प्रश्न
Neelaveni goes by bicycle to her school every day. Her average speed is 12 km/hr and she reaches school in 20 minutes. What is the increase in speed, If she reaches the school in 15 minutes?
Advertisements
उत्तर
Let the speed to reach school in 15 min be x
| Speed in Km/hr | 12 | x |
| Time in min | 20 | 15 |
∴ They are in inverse proportion
x1y1 = x2 y2
12 × 20 = x × 15
x = `(12 xx 20)/15`
x = 16
If she reaches in 15 min the speed = 16 km/hr
Already running with 12 km/hr
∴ Increased speed = 16 – 12 = 4 km/hr
Increase in speed = 4 km/hr
APPEARS IN
संबंधित प्रश्न
1200 soldiers in a fort had enough food for 28 days. After 4 days, some soldiers were transferred to another fort and thus the food lasted now for 32 more days. How many soldiers left the fort?
A person has money to buy 25 cycles worth Rs 500 each. How many cycles he will be able to buy if each cycle is costing Rs 125 more?
Raghu has enough money to buy 75 machines worth Rs 200 each. How many machines can he buy if he gets a discount of Rs 50 on each machine?
Mary cycles at 6 km per hour. How long will she take to reach her Aunt’s house which is 12 km away? If she cycles at a speed of 4 km/hr, how long would she take?
6 pumps are required to fill a water sump in 1 hr 30 minutes. What will be the time taken to fill the sump if one pump is switched off?
12 cows can graze a field for 10 days. 20 cows can graze the same field for _______ days
If xy = 10, then x and y vary ______ with each other.
When the speed is kept fixed, time and distance vary inversely with each other.
Length of a side of an equilateral triangle and its perimeter vary inversely with each other.
If d varies directly as t2, then we can write dt2 = k, where k is some constant.
