Selina solutions

Selina solutions

Selina solutions

Grade 7

CHAPTERS

3. Fractions (Including Problems)

4. Decimal Fractions (Decimals)

5. Exponents (including Laws of Exponents)

6. Ratio and Proportion (Including Sharing in a Ratio)

7. Unitary Method (including Time and Work)

11. Fundamental Concepts (Including Fundamental Operations)

12. Simple Linear Equations (Including Word Problems)

13. Set Concepts (Some Simple Divisions by Vedic Method)

14. Lines and Angles (Including Construction of angles)

17. Symmetry (Including Reflection and Rotation)

18. Recognition of Solids (Representing 3-D in 2-D)

Q11) 40 pens are bought at 4 for Rs. 50 and all of them are sold at 5 for Rs. 80

Find :

(i) C.P. of one pen.

(ii) S/P. of one pen.

(iii) Profit made by selling one pen.

(iv) Profit percent made by selling one pen.

(v) C.P. of 40 pens

(vi) S.P. of 40 pens.

(vii) Profit made by selling 40 pens.

(viii) Profit percent made by selling 40 pens. Are the results of parts (iv) and (viii) the same? What conclusion do you draw from the above result?

Solution:

(i) CP of 4 pen= Rs. 50

∴ CP of 40 pens = \frac{50\times40}{4}=Rs.500

And CP of 1 pen = \frac{500}{40}=Rs.\frac{25}{2}=Rs.12.50

(ii) SP of pens = Rs. 80

∴ SP of 1 pen = \frac{80}{5}=Rs.16

(iii) Profit pn 1 pen = SP - CP

=Rs. 16.00 - 12.50 = Rs. 3.50

(iv) Profit percent = \frac{\Pr ofit\times100}{CP}=\frac{3.50\times100}{12.50}=\frac{350\times100}{1250}=28\%

(v) CP of 40 pens = 40 x 12.50 = Rs. 500

(vi) SP of 40 pens = 40 x 16 = Rs. 640

(vii) Profit on 40 pens = SP - CP

= 640 - 500 = Rs. 140

(viii) Profit on 40 pens = \frac{\Pr ofit\times100}{CP}=\frac{140\times100}{500}=28\%

Yes, the results of (iv) and (viii) are the same.

We see that the profit of an equal number of articles remains the same.

Still have questions? Our expert teachers can help you out

Book a free class nowFractions (Including Problems)

Exponents (including Laws of Exponents)

Ratio and Proportion (Including Sharing in a Ratio)

Unitary Method (including Time and Work)

Fundamental Concepts (Including Fundamental Operations)

Simple Linear Equations (Including Word Problems)

Set Concepts (Some Simple Divisions by Vedic Method)

Lines and Angles (Including Construction of angles)

Symmetry (Including Reflection and Rotation)

Recognition of Solids (Representing 3-D in 2-D)

Q11) 40 pens are bought at 4 for Rs. 50 and all of them are sold at 5 for Rs. 80

Find :

(i) C.P. of one pen.

(ii) S/P. of one pen.

(iii) Profit made by selling one pen.

(iv) Profit percent made by selling one pen.

(v) C.P. of 40 pens

(vi) S.P. of 40 pens.

(vii) Profit made by selling 40 pens.

(viii) Profit percent made by selling 40 pens. Are the results of parts (iv) and (viii) the same? What conclusion do you draw from the above result?

Solution:

(i) CP of 4 pen= Rs. 50

∴ CP of 40 pens = \frac{50\times40}{4}=Rs.500

And CP of 1 pen = \frac{500}{40}=Rs.\frac{25}{2}=Rs.12.50

(ii) SP of pens = Rs. 80

∴ SP of 1 pen = \frac{80}{5}=Rs.16

(iii) Profit pn 1 pen = SP - CP

=Rs. 16.00 - 12.50 = Rs. 3.50

(iv) Profit percent = \frac{\Pr ofit\times100}{CP}=\frac{3.50\times100}{12.50}=\frac{350\times100}{1250}=28\%

(v) CP of 40 pens = 40 x 12.50 = Rs. 500

(vi) SP of 40 pens = 40 x 16 = Rs. 640

(vii) Profit on 40 pens = SP - CP

= 640 - 500 = Rs. 140

(viii) Profit on 40 pens = \frac{\Pr ofit\times100}{CP}=\frac{140\times100}{500}=28\%

Yes, the results of (iv) and (viii) are the same.

We see that the profit of an equal number of articles remains the same.

Still have questions? Our expert teachers can help you out

Book a free class nowLido

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