Class 7 · Chapter 8

Comparing Quantities

Percentages, profit and loss, simple interest.

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Detailed theory

x\%

means

x/100

. To find

p\%

of a value: multiply by

p/100

. Percentages compare on a per-100 basis, making comparison easy.

Key concepts & formulas

Percentage means 'per hundred':

x\% = \dfrac{x}{100}

\text{Profit\%} = \dfrac{\text{Profit}}{\text{CP}} \times 100

\text{Loss\%} = \dfrac{\text{Loss}}{\text{CP}} \times 100

SI = \dfrac{P\cdot R\cdot T}{100}

Amount

= P + SI