Question

A part of 8140 has been invested at a rate of interest of 4% pa. while the
remaining part has been invested at 5% p.a. Ir the amount that has been
invested at 5% pa is 3 times the other portion, then what will be the interest​

Answer 1

Answer:

386.65

Step-by-step explanation:

Total amount = 8140

Let the portion invested in 4% be x

Then the portion invested in5% = 3x

=> x + 3x = 8140

=> 4x = 8140

=> x = 8140/4

=> x = 2,035

Amount invested in 4% = 2035

Amount invested in 5% = 3(2,035) = 6105

Interest per year

Interest = (PTR)/100

Principle (P) = 2035 and 6105

Time (T) = 1 year

Rate (R) = 4 and 5

Interest in 4%

I = (2035×1×4) / 100

I = 8140/100

I = 81.4

Intetest in 5%

I = (6105×1×5)/100

I = 30525 / 100

I = 305.25

Total intetest = 81.4 + 305.25 = 386.65