A fruit seller sells 20 oranges for Tk. 900 and suffers a loss equal to the cost price of 5 oranges. Find the cost price of one orange.
A
Tk. 55
B
Tk. 60
C
Tk. 42
D
Tk. 62
উত্তরের বিবরণ
Question: A fruit seller sells 20 oranges for Tk. 900 and suffers a loss equal to the cost price of 5 oranges. Find the cost price of one orange.
Solution:
Let,
cost price of 1 orange is = Tk. x
∴ cost price of 20 oranges is = Tk. 20x
∴ cost price of 5 oranges is = Tk. 5x
We know,
Cost price - Selling price = Loss
20x - 900 = 5x
⇒ 20x - 5x = 900
⇒ 15x = 900
⇒ x = 900/15
∴ x = 60
∴ Cost price of 1 orange is Tk. 60
0
Updated: 1 month ago
At what rate of compound interest per annum will a sum of Tk. 4000 becomes Tk. 4840 in 2 years?
Created: 1 month ago
A
20%
B
10%
C
9%
D
12%
Question: At what rate of compound interest per annum will a sum of Tk. 4000 becomes Tk. 4840 in 2 years?
Solution:
Principal, P = Tk. 4000
Compound Amount, C = Tk. 4840
Time, n = 2 years
Rate, r = ?
We know,
C = P × (1 + r/100)n
⇒ 4840 = 4000 × (1 + r/100)2
⇒ (1 + r/100)2 = 4840/4000
⇒ (1 + r/100)2 = 484/400
⇒ 1 + r/100 = 22/20 [উভয়পাশে বর্গমূল করে]
⇒ r/100 = (11/10) - 1
⇒ r/100 = (11 - 10)/10
⇒ r/100 = 1/10
⇒ r = (1 × 100)/10
∴ r = 10
∴ Interest Rate = 10%
0
Updated: 1 month ago
The simple interest on a certain sum at 6% p.a. is Tk. 360 in 1 year. What will be the additional interest earned in 1 year if the rate increases to 7% p.a. on the same sum?
Created: 3 months ago
A
Tk. 60
B
Tk. 80
C
Tk. 70
D
Tk. 100
Solution:
Given,
Interest at 6% for 1 year:
Simple Interest, SI1 = Tk. 360
Interest rate, R = 6%
Time, T = 1 year (initial)
We know,
SI1 = PRT/100
⇒ 360 = (P × 6 × 1)/100
⇒ P = (360 × 100)/6
∴ P = Tk. 6000
So, the original sum (principal) is Tk. 6000.
Now,
Interest at 7% for 1 year:
SI2 = PRT/100
⇒ SI2 = (6000 × 7 × 1)/100
⇒ SI2 = Tk. 420
Additional interest = SI2 - SII
= 420 - 360
= Tk. 60
0
Updated: 3 months ago
What is the compound amount on a sum of Tk 10,000 for 2 years at 20% per annum, if the interest is compounded half-yearly?
Created: 1 month ago
A
Tk. 14,641
B
Tk. 14,520
C
Tk. 14,800
D
Tk. 15,225
এখানে, আসল (P) = 10,000 টাকা
বার্ষিক সুদের হার (r) = 20%
সময় (t) = 2 বছর
যেহেতু সুদ অর্ধবার্ষিক ভিত্তিতে (half-yearly) গণনা করা হয়, তাই প্রতি বছরে চক্রবৃদ্ধির সংখ্যা (n) = 2 বার।
এখন,
A = P{1 + r/(100 × 2)}nt
= 10,000 × (1 + 20/200)2 × 2
= 10,000 × (220/200)4
= 10,000 × (1.1)4
= 10,000 × 1.4641
= 14641 টাকা
∴ 2 বছর পর চক্রবৃদ্ধি মূল হবে 14,641 টাকা।
0
Updated: 1 month ago
