If P and Q together can complete a piece of work in 16 days and P alone in 24 days, in how many days can Q alone complete the work?
A
72 days
B
48 days
C
42 days
D
36 days
উত্তরের বিবরণ
Question: If P and Q together can complete a piece of work in 16 days and P alone in 24 days, in how many days can Q alone complete the work?
Solution:
P and Q complete a work in = 16 days
One day's work of (P + Q) = 1/16
P complete the work in = 24 days;
One day's work of P = 1/24
Then, Q's one day's work = (1/16) - (1/24)
= (3 - 2)/48
= 1/48
So, Q alone can complete the work in = 48 days.
0
Updated: 2 months ago
Rahim and Karim can finish a work together in 6 hours. If Rahim takes 3 times as long as Karim to finish the job alone, how long will Karim take to finish the job alone?
Created: 1 month ago
A
9 hours
B
8 hours
C
12 hours
D
15 hours
Question: Rahim and Karim can finish a work together in 6 hours. If Rahim takes 3 times as long as Karim to finish the job alone, how long will Karim take to finish the job alone?
Solution:
ধরি, করিম একা কাজটি শেষ করতে সময় নেয় = x ঘন্টা
রহিম একা কাজটি শেষ করতে সময় নেয় = 3x ঘন্টা
এখন,
করিমের 1 ঘন্টার কাজের পরিমাণ = 1/x অংশ
রহিমের 1 ঘন্টার কাজের পরিমাণ = 1/(3x) অংশ
তারা একসাথে 1 ঘন্টায় কাজ করতে পারে = (1/x) + 1/(3x)
= (3+1)/(3x)
= 4/(3x) অংশ
একসাথে কাজটি শেষ করতে সময় লাগে = 6 ঘন্টা
অর্থাৎ, 6 ঘন্টায় তারা পুরো 1টি কাজ শেষ করে
তাহলে,
(4/3x) × 6 = 1
⇒ 24/(3x) = 1
⇒ 8/x = 1
⇒ x = 8
∴ করিমের কাজটি একা শেষ করতে 8 ঘন্টা সময় লাগবে।
0
Updated: 1 month ago
3/7 part of the tank is full of water. When 42 liters of water is taken out, the tank becomes empty. The capacity of the tank is -
Created: 2 months ago
A
82 liters
B
66 liters
C
78 liters
D
98 liters
Question: 3/7 part of the tank is full of water. When 42 liters of water is taken out, the tank becomes empty. The capacity of the tank is -
Solution:
Let us consider,
The tank has 7x liters of total capacity and holds 3x litres of water.
And if 42 liters of water is taken out, then the tank becomes empty.
It means 3x litres of water is taken out.
∴ 3x = 42 liters
⇒ x = 14 liters
∴ Capacity of tank = 7x = 7 × 14 = 98 liters
0
Updated: 2 months ago
Anik alone can do a piece of work in 6 days and Bishal alone in 8 days. Anik and Bishal undertook to do it for Tk. 5400. With the help of Dinesh, they completed the work in 3 days. How much is to be paid to Dinesh?
Created: 2 months ago
A
Tk. 675
B
Tk. 900
C
Tk. 870
D
Tk. 780
Question: Anik alone can do a piece of work in 6 days and Bishal alone in 8 days. Anik and Bishal undertook to do it for Tk. 5400. With the help of Dinesh, they completed the work in 3 days. How much is to be paid to Dinesh?
Solution:
Anik's 1day work = 1/6
Bishal's 1 day work = 1/8
∴ (Anik + Bishal + Dinesh)'s 1 day work = 1/3
∴ Dinesh's 1 day work = (1/3) - (1/6) - (1/8) = (8 - 4 - 3)/24 = 1/24
So, Dinesh's 3 day work = 3 × (1/24) = 1/8
If Dinesh contributed 8th part of work then he will receive 8th part of total payment
∴ Dinesh should be paid = 5400 × (1/8) = Tk. 675
0
Updated: 2 months ago
