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According to the given statement, the perimeter of the plot is 154 m.

\ 4x + 18 = 154

or 4x = 136 [Transposing + 18 to RHS as –18]

136
⇒ x = = 34 [Transposing × 4 to RHS as ÷ 4]
4

Thus, the breadth of the rectangular plot = 34 m and

the length of the rectangular plot = (x + 9) = (34 + 9) m = 43 m

Example 12: Grandfather gives a potli bag to Pihu, in the bag, the number of `5 coins is four times
the number of `2 coins. If the worth of the coins is `110, find the number of `5 coins.

Solution: Let the number of `2 coins be x.

Then, the number of `5 coins be 4x.

According to the given statement,
2x + 5(4x) = 110

2x + 20x = 110
22x = 110

110
x = = 5 [Transposing × 22 to RHS as ÷ 22]
22

Therefore, `5 coins in the potli bag = 4 × x = 4 × 5 = 20
Thus, the number of five rupee coins is 20.

Example 13: A man travelled two-fifth of his journey by train, one-third by
bus, one-fourth by car and the remaining 3 km on foot. What is the length
of his total journey?

Solution: Let the length of his total journey be x km.

2x x x
Then, his journey by train be km, by bus be km and by car be km.
5 3 4

According to the given statement,
2x x x
x = + + + 3
5 3 4

2x x x
⇒ x – − − = 3 Think and Answer
5 3 4 Think a number and take 7 times
x of it and add a half-century in it to get a triple
⇒ = 3
60 century. What number did you think?
⇒ x = 180
Thus, the total length of his journey is 180 km.

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