Pair Of Linear Equations In Two Variables Question - CBSE_NCERT_TEXTBOOK

Question

Champa went to a ‘Sale’ to purchase some pants and skirts. When her friends asked her how many of each she had bought, she answered, “The number of skirts is two less than twice the number of pants purchased. Also, the number of skirts is four less than four times the number of pants purchased”. Help her friends to find how many pants and skirts Champa bought.

Accepted Answer

1. Introduce variables
Let $p$ be the number of pants and $s$ be the number of skirts.

2. Translate the statements into equations
- "The number of skirts is two less than twice the number of pants" gives $$ s = 2p - 2 $$
- "The number of skirts is four less than four times the number of pants" gives $$ s = 4p - 4 $$

3. Equate the two expressions for $s$
$$ 2p - 2 = 4p - 4 $$

4. Solve for $p$
$$ 2p - 2 = 4p - 4 $$
$$ -2p = -2 $$
$$ p = 1 $$

5. Find $s$ using any one of the original equations
Using $s = 2p - 2$:
$$ s = 2(1) - 2 = 0 $$
(The same value is obtained from $s = 4p - 4$.)

6. State the answer
Champa bought 1 pant and 0 skirts.

Question:

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