Ganesh purchased an industrial land at Rs [tex]$1,60,00,000$[/tex] and a printing machine at Rs [tex]$5,40,00,000$[/tex]. If the value of the land increases at [tex]$20\%$[/tex] p.a. and the value of the machine depreciates at [tex]$20\%$[/tex] p.a. (compounded annually):

(a) Define compound growth of price.

[tex]\[P_{G} = P \left(1+\frac{R}{100}\right)^T - P\][/tex]

(b) What will be the value of the land after 2 years?

Ans: Rs [tex]$2,30,40,000$[/tex]

(c) What will be the value of the machine after 2 years?

Ans: Rs [tex]$3,45,60,000$[/tex]

(d) In how many years will the value of the machine and the value of the land be equal?

Ans: 3 years

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२गणशले एउटा औद्योगिक जमिन रु. [tex]$1,60,00,000$[/tex] मा र एउटा छपाइ मेशिन रु. [tex]$5,40,00,000$[/tex] मा खरिद गयो । यदि सो जमिनको मूल्य [tex]$20\%$[/tex] प्रति वर्षको दरमा बढछ र मेशिनको मूल्य [tex]$20\%$[/tex] प्रति वर्षको दरमा घट्दछ (वार्षिक चक्रीय अनुसार) भने:

(a) चक्रीय मूल्य वृद्धिलाई परिभाषित गर्नुहोस् ।

[tex]\[P_{G} = P \left(1+\frac{R}{100}\right)^T - P\][/tex]

(b) 2 वर्षपछि सो जमिनको मूल्य पत्ता लगाउनुहोस् ।

उत्तर: रु. [tex]$2,30,40,000$[/tex]

(c) 2 वर्षपछि सो मेशिनको मूल्य पत्ता लगाउनुहोस् ।

उत्तर: रु. [tex]$3,45,60,000$[/tex]

(d) कति वर्षमा मेशिनको मूल्य र जमिनको मूल्य बराबर होलान् ?

उत्तर: 3 वर्ष



Answer :

Let's systematically work through the problem step-by-step:

Given:
1. Ganesh purchased industrial land at Rs. [tex]$1,60,00,000$[/tex].
2. He also purchased a printing machine at Rs. [tex]$5,40,00,000$[/tex].
3. The value of the land increases at a rate of [tex]$20\%$[/tex] per annum (compounded annually).
4. The value of the machine decreases at a rate of [tex]$20\%$[/tex] per annum (compounded annually).

Part (a): Define compound growth of price.

The compound growth of price [tex]\( P_G \)[/tex] is the increase in value over time, which can be described by the formula:
[tex]\[ P_G = P \left(1 + \frac{R}{100}\right)^T - P \][/tex]

Similarly, depreciation [tex]\( P_D \)[/tex] for a decreasing value over time is given by:
[tex]\[ P_D = P - P \left(1 - \frac{R}{100}\right)^T \][/tex]

Part (b): What will be the value of the land after 2 years?

To find the value of the land after [tex]\( T = 2 \)[/tex] years with an initial value of Rs. [tex]$1,60,00,000$[/tex] and an annual growth rate of [tex]$20\%$[/tex], we use the compound interest formula:
[tex]\[ V_{\text{land}} = P \left(1 + \frac{R}{100}\right)^T \][/tex]
[tex]\[ V_{\text{land\_2years}} = 1,60,00,000 \left(1 + \frac{20}{100}\right)^2 \][/tex]

Calculating it, we get:
[tex]\[ V_{\text{land\_2years}} = 1,60,00,000 \left(1.2\right)^2 \][/tex]
[tex]\[ V_{\text{land\_2years}} = 1,60,00,000 \times 1.44 \][/tex]
[tex]\[ V_{\text{land\_2years}} = 2,30,40,000 \][/tex]

So, the value of the land after 2 years will be Rs. [tex]$2,30,40,000$[/tex].

Part (c): What will be the value of the machine after 2 years?

To find the value of the machine after [tex]\( T = 2 \)[/tex] years with an initial value of Rs. [tex]$5,40,00,000$[/tex] and an annual depreciation rate of [tex]$20\%$[/tex], we use the depreciation formula:
[tex]\[ V_{\text{machine}} = P \left(1 - \frac{R}{100}\right)^T \][/tex]
[tex]\[ V_{\text{machine\_2years}} = 5,40,00,000 \left(1 - \frac{20}{100}\right)^2 \][/tex]

Calculating it, we get:
[tex]\[ V_{\text{machine\_2years}} = 5,40,00,000 \left(0.8\right)^2 \][/tex]
[tex]\[ V_{\text{machine\_2years}} = 5,40,00,000 \times 0.64 \][/tex]
[tex]\[ V_{\text{machine\_2years}} = 3,45,60,000 \][/tex]

So, the value of the machine after 2 years will be Rs. [tex]$3,45,60,000$[/tex].

Part (d): In how many years will the value of the machine and the value of the land be equal?

To find the time [tex]\( T \)[/tex] where the values are equal, we set up the equation:
[tex]\[ 1,60,00,000 \left(1 + \frac{20}{100}\right)^T = 5,40,00,000 \left(1 - \frac{20}{100}\right)^T \][/tex]

Simplifying, we get:
[tex]\[ \left(1.2\right)^T = \frac{5,40,00,000}{1,60,00,000} \left(0.8\right)^T \][/tex]
[tex]\[ \left(1.2\right)^T = 3.375 \left(0.8\right)^T \][/tex]

Using logarithms to solve for [tex]\( T \)[/tex]:
[tex]\[ \log \left(1.2^T \right) = \log \left(3.375 \left(0.8\right)^T \right) \][/tex]
[tex]\[ T \cdot \log (1.2) = \log (3.375) + T \cdot \log (0.8) \][/tex]
[tex]\[ T \cdot (\log (1.2) - \log (0.8)) = \log (3.375) \][/tex]
[tex]\[ T = \frac{\log (3.375)}{\log (1.2) - \log (0.8)} \][/tex]

Solving this, we find:
[tex]\[ T = 3 \][/tex]

So, the value of the land and the machine will be equal in 3 years.

Summary of Answers:
(a) Compound growth of price is defined using the formula [tex]\( P_G = P (1 + \frac{R}{100})^T - P \)[/tex] for growth and [tex]\( P_D = P - P (1 - \frac{R}{100})^T \)[/tex] for depreciation.
(b) The value of the land after 2 years will be Rs. [tex]$2,30,40,000$[/tex].
(c) The value of the machine after 2 years will be Rs. [tex]$3,45,60,000$[/tex].
(d) The value of the land and the machine will be equal in 3 years.