A worker earns Tk. 300 on the first day and spends Tk. 150 on the second day, earns Tk. 300 on the third day and again spends Tk. 150 on the fourth day, and so on. On which day would he have had Tk. 1500?
A
16th day
B
17th day
C
19th day
D
21st day
উত্তরের বিবরণ
Question: A worker earns Tk. 300 on the first day and spends Tk. 150 on the second day, earns Tk. 300 on the third day and again spends Tk. 150 on the fourth day, and so on. On which day would he have had Tk. 1500?
Solution:
1ম দিনে আয় = 300 টাকা
2য় দিনে ব্যয় = 150 টাকা
∴ প্রতি 2 দিনে জমা হয় = 300 - 150 = 150 টাকা
শুধু 1ম দিনে আয় করায় হাতে থাকে = 300 টাকা
অতএব, 1500 - 300 = 1200 টাকা আরও জমা করতে হবে।
150 টাকা জমা হয় 2 দিনে,
∴ 1200 টাকা জমা হয় = (2 × 1200)/150 = 16 দিনে
অর্থাৎ, 16 দিনের শেষে জমা থাকবে = 1200 টাকা
17-তম দিনে আবার আয় হবে = 300 টাকা
∴ মোট সঞ্চয় হবে = 1200 + 300 = 1500 টাকা
∴ 17-তম দিনে তার কাছে মোট 1500 টাকা জমা থাকবে।
0
Updated: 1 week ago
P and Q can do a job in 3 days. Q and R can do the same job in 4 days, while R and P can do it in 12 days. In how many days the job will be finished when P, Q and R working together.
Created: 2 weeks ago
A
10 days
B
3 days
C
4 days
D
12 days
Question: P and Q can do a job in 3 days. Q and R can do the same job in 4 days, while R and P can do it in 12 days. In how many days the job will be finished when P, Q and R working together.
Solution:
Given that,
(P + Q)'s 1 day's work = 1/3
(Q + R )'s 1 day's work= 1/4
and
(R + P)'s 1 day's work = 1/12
Now, (P + Q) + (Q + R) + (R + P) = 2(P + Q + R)'s 1 day's work = (1/3) + (1/4) + (1/12)
= (4 + 3 + 1)/12
= 8/12 = 2/3
∴ (P + Q + R)'s 1 day's work = 2/(3 × 2) = 1/3
So, P + Q + R can complete the job in = 3 days
0
Updated: 2 weeks ago
Hasan can dig 18 holes in 12 minutes. Faruk can dig the same number of holes in only 6 minutes. Hasan digs the first 9 holes, then Faruk digs for 2 minutes, and finally Hasan finishes the remaining holes. How long will it take them to dig 27 holes in total?
Created: 1 week ago
A
10 minutes
B
16 minutes
C
18 minutes
D
21 minutes
Question: Hasan can dig 18 holes in 12 minutes. Faruk can dig the same number of holes in only 6 minutes. Hasan digs the first 9 holes, then Faruk digs for 2 minutes, and finally Hasan finishes the remaining holes. How long will it take them to dig 27 holes in total?
Solution:
Faruk can dig 18 holes in 6 minutes.
∴ In 2 minutes, he can dig = (18 × 2)/6 holes
= 6 holes
Hasan first digs 9 holes.
∴ Total completed = 9 (Hasan) + 6 (Faruk) = 15 holes
Remaining = 27 - 15 = 12 holes
Hasan can dig 18 holes in 12 minutes.
∴ To dig 12 holes, Hasan will take = (12 × 12) / 18 = 8 minutes
Time Hasan spent digging first 9 holes = (12 × 9)/18 = 6 minutes
∴ Total time = 6 (Hasan) + 2 (Faruk) + 8 (Hasan) = 16 minutes
0
Updated: 1 week ago
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?
Created: 1 week ago
A
15 hours
B
20 hours
C
18 hours
D
16 hours
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
