Question

a sumof rs 800is lent for one year at the rate of 18%per annum the interest

Answer 1

Principle = 800
Rate = 18%
Time = 1year
SI = p×r×t/100
SI = 800×18×1/100 = 144
Amount = (800+144) = 944

Answer 2

Step-by-step explanation:

Solution :

Let the number of 10 rupees note be x and 20 rupees not be ( 50 - x)

Total sum = 800

Now,

10 rupee notes = 10x and

20 rupee notes = 20(50 - x)

According to the question :

$\longrightarrow \sf \: 10x + 20(50 - x) = 800⟶10x+20(50−x)=800</p><p></p><p>[tex]\longrightarrow \sf \:$10x + 1000 - 20x = 800⟶10x+1000−20x=800

$\longrightarrow \sf \:$ 10x - 20x + 1000= 800⟶10x−20x+1000=800

$\longrightarrow \sf \:$- 10x = 800 - 1000⟶−10x=800−1000

$\longrightarrow \sf \:$ - 10x = - 200⟶−10x=−200

$\longrightarrow \sf \:$x = \dfrac{200}{10}⟶x=

10

200

$\longrightarrow \sf \:$x =20⟶x=20

$\therefore∴$ Number of 10 rupee notes = 20 and number of 20 rupee notes = (50 - 20) = 30