How many years will Tk. 1500 need at 4% simple interest to earn the same interest as Tk. 2000 earns in 3 years at 5% simple interest?
A
4 years
B
5 years
C
6 years
D
8 years
উত্তরের বিবরণ
Question: How many years will Tk. 1500 need at 4% simple
interest to earn the same interest as Tk. 2000 earns in 3 years at 5% simple
interest?
Solution:
Interest from Tk. 2000 in 3 years at 5%:
SI = (P × R × T)/100
= (2000 × 5 × 3)/100
= 300 Tk.
Now,
Tk. 1500 to Produce the Same Interest (Tk. 300) at 4%:
Principal, P = Tk. 1500
Interest, SI = Tk. 300
Interest Rate, R = 4%
Time, T = ? years
SI = PRT/100
⇒
T = (SI × 100)/(P × R)
⇒
T = (300 × 100)/(1500 × 4)
⇒
T = 30000/6000
∴
T = 5 years
0
Updated: 8 hours ago
Two numbers are in the ratio 2 : 3. If 4 is subtracted from the first number, the ratio becomes 1 : 2. What are the numbers?
Created: 8 hours ago
A
14, 21
B
16, 24
C
18, 27
D
20, 30
Question: Two numbers are in the ratio 2 : 3. If 4 is
subtracted from the first number, the ratio becomes 1 : 2. What are the
numbers?
Solution:
Let the two numbers be: 2x and 3x
According to the question,
(2x - 4)/3x = 1/2
⇒
2(2x - 4) = 3x
⇒
4x - 8 = 3x
⇒
x = 8
∴ First number = 2 × 8
= 16
∴
Second number = 3 × 8 = 24
0
Updated: 8 hours ago
At what rate of compound interest per annum will a sum of Tk. 1600 becomes Tk. 2304 in 2 years?
Created: 8 hours ago
A
20%
B
15%
C
12%
D
30%
Question: At what rate of compound interest per annum will a
sum of Tk. 1600 becomes Tk. 2304 in 2 years?
Solution:
Principal, P = 1600 টাকা
Amount, A = 2304 টাকা
Time, n = 2 years
Rate, r = ?
We know,
A = P × (1 + r/100)n
⇒
2304 = 1600 × (1 + r/100)2
⇒
(1 + r/100)2 = 2304/1600
⇒
(1 + r/100) = 48/40 [উভয়পাশে
বর্গমূল করে]
⇒
1 + r/100 = 6/5
⇒
r/100 = 6/5 - 1
⇒
r/100 = (6 - 5)/5
⇒
r/100 = 1/5
⇒
r = 100/5
∴
r = 20
∴ Interest rate 20%
0
Updated: 8 hours ago
The ratio of milk and water in a solution is 7 : 4. After adding 8 liters of water, the ratio of milk and water becomes 3 : 2. Find the final amount of water in the solution.
Created: 8 hours ago
A
48 liters
B
54 liters
C
56 liters
D
60 liters
Question: The ratio of milk and water in a solution is 7 :
4. After adding 8 liters of water, the ratio of milk and water becomes 3 : 2.
Find the final amount of water in the solution.
Solution:
Let the initial amount of milk = 7x liters
Let the initial amount of water = 4x liters
According to the question,
7x/(4x + 8) = 3/2
⇒
2 × 7x = 3 ×
(4x + 8)
⇒
14x = 12x + 24
⇒
14x - 12x = 24
⇒
2x = 24
⇒
x = 12
∴ Final amount of water = 4x + 8
= 4 × 12 + 8
= 48 + 8 = 56 liters
0
Updated: 8 hours ago
