5 pumps working 6 hours a day can empty a tank in 3 days. How many hours a day must 3 pumps work to empty the tank in 2 days?
A
15 hours
B
20 hours
C
18 hours
D
16 hours
উত্তরের বিবরণ
Question: 5 pumps working 6 hours a day can empty a tank in 3 days. How many hours a day must 3 pumps work to empty the tank in 2 days?
Solution:
5 pumps এর প্রয়োজনীয় সময় 3 × 6 = 18 ঘণ্টা
1 pump এর প্রয়োজনীয় সময় = 18 × 5 = 90 ঘণ্টা
3 pumps এর প্রয়োজনীয় সময় = 90/3 = 30 ঘণ্টা
∴ 3টি পাম্পকে 2 দিনে কাজটি শেষ করতে প্রতিদিন কাজ করতে হবে,
= (30/2) = 15 ঘণ্টা।
0
Updated: 1 week ago
If 10 men or 18 women can do a work in 50 days then how many days would it take 25 men and 15 women to do twice the work?
Created: 2 weeks ago
A
25 days
B
30 days
C
32 days
D
40 days
Question: If 10 men or 18 women can do a work in 50 days then how many days would it take 25 men and 15 women to do twice the work?
Solution:
Here,
10 men = 18 women
∴ 1 men = 18/10 women
∴ 25 men = (18 × 25)/10 women
= 45 women
∴ 25 men and 15 women = (45 + 15) = 60 women
ATQ,
18 women can do the work in 50 days
∴ 1 women can do the work in = (50 × 18) days
∴ 60 women can do the work in (50 × 18)/60 days
= 15 days
Hence to do twice the work time need = (15 × 2) = 30 days
0
Updated: 2 weeks ago
Rafi and Shafi can paint a room in 4 days. Shafi can do it alone in 6 days. How many days will Rafi take to paint the room alone?
Created: 1 week ago
A
12 days
B
10 days
C
15 days
D
9 days
Question: Rafi and Shafi can paint a room in 4 days. Shafi can do it alone in 6 days. How many days will Rafi take to paint the room alone?
Solution:
ধরা যাক,
Rafi একা কাজটি করতে x দিন সময় নেন।
∴ Rafi-র 1 দিনের কাজ = 1/x
∴ Shafi-র 1 দিনের কাজ = 1/6 (কারণ সে একা ৬ দিনে কাজটি করে)
তারা দুজনে মিলে ৪ দিনে কাজ শেষ করে।
∴ তাদের 1 দিনের একত্রে কাজ = 1/4
এখন,
(1/x) + (1/6) = 1/4
⇒ (6 + x) / (6x) = 1/4
⇒ 4(6 + x) = 6x
⇒ 24 + 4x = 6x
⇒ 24 = 6x - 4x = 2x
⇒ x = 24 / 2 = 12
∴ Rafi একা কাজটি করতে 12 দিন সময় নেবে।
0
Updated: 1 week ago
A canteen requires 105 kgs of wheat for a week. How many kgs of wheat will it require for 58 days?
Created: 2 weeks ago
A
840 kgs
B
950 kgs
C
620 kgs
D
870 kgs
Question: A canteen requires 105 kgs of wheat for a week. How many kgs of wheat will it require for 58 days?
Solution:
For 7 days it is required = 105 kgs
∴ For 1 days it is required = (105/7) kgs
∴ For 58 days it is required = (105 × 58)/7 = 870 kgs
∴ 870 kilograms of wheat will be required for 58 days.
0
Updated: 2 weeks ago
