# Exercise : 3

(b) 25,000

(c) 20,000

(d) 24,000

(e) None of these

**Ans.c**

Let the amount invested at 20% rate be x. According to the question,

12000 × ^{10}⁄_{100} + x × ^{20}⁄_{100} = (12000 + x) × ^{14}⁄_{100}

or, 1200 + ^{x}⁄_{5} = 1680 + ^{7}⁄_{50}x

or, ^{x}⁄_{5} - ^{7}⁄_{50}x = 480

or, ^{3}⁄_{50}x = 480

\ x = 8000

\ Total amount invested = (12000 + 8000)= 20000

(b) 13,210

(c) 13,320

(d) 13,120

(e) None of these

**Ans.e**

Amount = 10000(1 + ^{10}⁄_{100})^{3}

= 10000 × ^{11}⁄_{10} × ^{11}⁄_{10} × ^{11}⁄_{10}

= 13310

(b) 10,000

(c) 8,000

(d) Data inadequate

(e) None of these

**Ans.c**

Let ‘x’ be the amount borrowed by Nelson

and \(\frac{x \times 6 \times 3}{100} + \frac{x \times 9 \times 5}{100} + \frac{x \times 13 \times 3}{100} = 8160\)

⇒ ^{102}⁄_{100}x = 8,160

∴ x = \(\frac{8,160 \times 100}{102} = 8000\)

(a) 6 p.c. p.a. for the first three years

(b) 8 p.c. p.a. for the next five years

(c) 12 p.c. p.a. for the next eight years

If he paid a total of 5,040 as interest at the end of twelve years, how much money did he borrow?

(b) 10,000

(c) 12,000

(d) 6,000

(e) None of these

**Ans.e**

Let x be the amount Amal borrowed.

∴ 18% of x + 40% of x + 48% of x = 5040

or, 106% of x = 5040

∴ x = ^{5040}⁄_{106} × 100 = 4754.71

(b) 25000

(c) 7500

(d) 14500

(e) None of these

**Ans.a**

Let the amount be x.

From the question, \(\frac{x \times 14 \times 6}{1200} - \frac{x \times 8 \times 8}{1200}\) = 250

∴ x = 15000

(b) 2,500

(c) 2,550

(d) 2,600

(e) None of these

**Ans.b**

Let S.I. = x

= \(\frac{1.53 \times 10^{5} \times 20}{100}\)

= 2,500

(b) 600

(c) 700

(d) 800

(e) None of these

**Ans.c**

Difference in S.I. = \(\frac{P \times T}{100} \left(R_{1} - R_{2} \right)\)

⇒ 56 = \(\frac{P \times 4 \times 2}{100}\) (∵ R_{1} - R_{2} = 2)

⇒ P = \(\frac{56 \times 100}{4 \times 2} = 700\)

(b) 6% and 6 years

(c) 10% and 10 years

(d) 12 % and 12 years

(e) None of these

**Ans.a**

^{16}⁄_{25}P = \(\frac{P \times R \times R}{100}\)

⇒ R^{2} = ^{1600}⁄_{25} ⇒ R = ^{40}⁄_{5} = 8%

Also, time = 8 years

(b) 7

(c) 35

(d) 30.50

(e) None of these

**Ans.a**

∵ Rate = 5 paise per rupee = 5%

∴ S.I. = \(\frac{200 \times 5 \times 7}{100} = 70\)

(b) 28,000, 40,000

(c) 32,000, 36,000

(d) Cannot be determined.

(e) None of these

**Ans.c**

Let one gets = x

then, second gets = (68,000 – x)

Given : A_{1} = A_{2}

⇒ x[100 + 80] = (68,000 - x)[100 + 60]

⇒ ^{180}⁄_{160}x = 68,000 - x

⇒ 34x = 68000 × 16 ⇒ x = 32000

∴ second gets = 36,000