# Grade 8 Commercial Math Worksheet (For CBSE, ICSE, IAS, NET, NRA 2022)

Doorsteptutor material for CBSE/Class-8 is prepared by world's top subject experts: get questions, notes, tests, video lectures and more- for all subjects of CBSE/Class-8.

## (1) Answer the Following Questions. (Round off Your Answer to Two Decimal Places Wherever Necessary)

⚹⚹ ⚹ Rekha buy four apple for ₹ 200 each. She sells first two apples at a loss of 10 % . she sells other two apples such that gain percent on the overall transaction is 10 % .

(a) What is the selling price of first two apples?

(b) What is the selling price of other two apples?

(c) What is the profit percentage on the sale of each of the other two apples?

## (2) Rohit Sells His Bike at a Second Hand Price but He Still Manages to Make Profit of 20 % . If He Sold It for ₹ 500 More Than Profit Would Have Been 30 %

(a) Find the cost price of Bike.

(b) If bike had been sold for ₹ 800 more, what would have been the profit percent?

## (3) a Retailer of a Furniture Shop Offers a Discount of 30 % on All Items. On Diwali Sale He Offers Another 20 % Discount on Already Discounted Price. Find the Percentage of Discount Equivalent to the Total Effect of the Two Discounts

## (4) Vikas Bought Following Item from a Store

Item | Quantity (Packet) | Basin selling price per unit (packet) | Sales Tax. |

wafer | 5 | 30 | 10 % |

juice | 2 | 90 | 18 % |

chocolate | 6 | 40 | 20 % |

Find total amount which Vikas had to pay for these items.

## (5) Find the Compound Interest for ₹ 20800 Invested at the Interest Rate of 7 % Per Annum for 3 Years

## (6) Neha Borrows ₹ 505000 from Prashant, at the Interest Rate of 10 % Per Annum Compounded Annually for the Period of 3 Years. Find the Compound Interest and the Amount That Needs to be Paid Back After Three Years

(7) Find the compound interest on ₹ 9000 at the rate of 7 % per annum for years, when the interest is compounded half-yearly.

(Take

## (8) Ramesh Borrowed ₹ 2,00, 000 from Aditya at 10 % Per Annum Simple Interest. He Lent this Amount to Kishor at 10 % Per Annum Interest Compounded Annually. After Two Years

## [Take (1.1) ^{2} = 1.21]

(a) How much does Ramesh need to pay to Aditya?

(b) How much money would he receive from Kishor?

(c) What is Ramesh՚s gain?

(9) What sum of money will amount to at per annum in 3 years, interest being compounded annually?

## (10) Seema Taken Loan of 1,50, 000 at an Interest Rate of 15 % Per Annum, Compounded Annually. When the Term of Loan is Completed, She Pays Back ₹ 3,01, 703.578. Find the Duration of Loan

## (11) a Bank Offer Interest Rate of 9 % Per Annum in Year-1 and 12 % Per Annum in Year-2. The Compounding is Done Semi-Annually. If One Invests 50000 at the Beginning of Year-1, How Much Would He Get at the End of Year-2? [Take (1.045) ^{2} = 1.09 and (1.06) ^{2} = 1.12]

## (12) the Population of Ahmadabad City Grows at a Rate of 20 % Per Annum. If Population Today is 20,60, 800 Roughly What Would Its Population Have Been Two Years Ago?

## Answers and Explanations

### Answer 1 (A)

- Rekha buy four apples for ₹ 200 each.
- So she paid total to buy apple.
- Now, she sells first two apples at a loss of 10 % .
- Buying price of two apple
- Now,

- She had a loss of

- So, selling price of first two apple
- Therefore, selling price of first two apple is

### Answer 1 (B)

- Now, sells other two apples such that gain percent on the overall transaction is 10 % .
- Considering over all transaction total buying price of apple is

- So, Rekha had total gain
- So, selling price of other two apple is
- Selling price of other two apple
- Selling price of other two apple

### Answer 1 (C)

- Selling price of other two apples
- So, selling price of Single apple
- Now, buying price of apple
- So, total profit per apple
- So,

- So Profit percentage

### Answer 2 (A)

- Suppose Rohit purchase his bike at a cost of
- On selling his bike second hand he still manages to make profit 20 % .
- So,

- Selling price of bike

- Now, to make 30 % profit the selling price of bike should be,

- Selling price of bike

- Now, If Rohit sold his bike for ₹ 500 more than profit would have been 30 % .

- So Buying price of bike

### Answer 2 (B)

- Now, if bike had been sold ₹ 800 more than selling price

- Now,

- So, Profit Percent

- So, if bike had been sold for ₹ 800 more than Profit percent is

### Answer 3

- Here initial offered discount
- So
- Now, on Diwali sale another 20 % discount added on already discounted price.
- So,
- Now, formula for percentage of discount equivalent to the total effect of the two discounts.

- Percentage of discount equivalent to the total effect of the two discounts is .

### Answer 4

Item | Quantity (Packet) | Basin selling price per unit (packet) | selling price | Sales Tax. |

wafer | 5 | 30 | 10 % | |

juice | 2 | 90 | 18 % | |

chocolate | 6 | 40 | 20 % |

- Now for wafer sales tax is 10 % .

- Final sales price of wafer/amount paid by Vikas for wafer

- Now for juice sales tax is 18 % .

- Final sales price of Juice/amount paid by Vikas for juice

- Now for Chocolate sales tax is 20 % .

- Final sales price of Chocolate/amount paid by Vikas for Chocolate

- So, total amount paid by Vikas

- So, total amount paid by Vikas is
**₹ 665.4**

### Answer 5

- Formula for Compound interest
- Where, Principal amount , in our case

, Interest rate in percentage terms, in our case

, Number of compounding period, in our case .

- Compound Interest

- So, Compound interest for 3 years is

### Answer 6

- Formula for Compound interest
- Where, Principal amount, in our case

, Interest rate in percentage terms, in our case

, Number of compounding period, in our case .

- Compound Interest

**So, Compound Interest is**- So, Total amount that needs to be paid back after three year by Neha is

- So, Neha needs to pay back after 3 years.

### Answer 7

- Formula for Compound interest:

- Where,

Final amount, in our case A is unknown means we have to find A

Principal Amount, in our case

Interest Rate, in our case

Number of times interest applied per time period, in our case because interest count half yearly

Number of time periods elapsed, in our case

- So,

- Compound interest

- So, Compound Interest is
**₹ 981**.

### Answer 8 (A)

- Ramesh borrowed from Aditya at per annum simple interest for 2 year.
- So, Formula for Simple interest,

- Where, Final Amount, in our case amount Ramesh needs to pay to Aditya.

initial Principal Amount, in our case

Interest Rate, in our case

time period, in our case years.

- Hence,

- So, at the end of two years Ramesh need to pay to Aditya

### Answer 8 (B)

- Ramesh lent to Kishor at the interest rate of 10 % for two years, interest calculated compound.
- Formula for compound interest,

- Where, Final amount, in our case the amount Ramesh received from Kishor.

Principal Amount, in our case

interest Rate, in our case

number of times interest applied per time period, in our case because interest count yearly

Number of time periods elapsed, in our case

- So,

- So, Ramesh received from Kishor.

### Answer 8 (C)

- Total amount gain by Ramesh

- So, Total amount gain by Ramesh is .

### Answer 9

- Formula for Compound interest:

- Where,

Final amount, in our case

Principal Amount, in our case P is unknown.

Interest Rate, in our case

Number of times interest applied per time period, in our case because interest count yearly

Number of time periods elapsed, in our case

- So,

- So, Principle amount is
**₹ 782122.90**

### Answer 10

- Formula for Compound interest:

- Where,

Final amount, in our case

Principal Amount, in our case .

Interest Rate, in our case

Number of times interest applied per time period, in our case because interest count half yearly

Number of time periods elapsed, in our case is unknown.

- So,

- Therefore, duration of loan is
**5 years**.

### Answer 11

- For 1
^{st}year

- So,

- So, at the end of year-1 amount will be
- Now for 2
^{nd}year,

- Now,

- So, at the end of year-2 one can get

### Answer 12

- Here from the given data, it՚s a sum of simple interest.
- Formula for Simple interest,

- Where,

Final Amount; in our case current population of Ahmadabad city

initial Principal Amount; in our case P is unknown, the population of Ahmadabad two years ago.

Interest Rate, in our case

Time period, in our case .

- So,

- So, population of Ahmadabad city two year ago was .