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प्रश्न
There are two beautiful lakes near a village. People come for boating and picnics in both the lakes. The village Panchayat is worried that with the noise of the boats the birds will stop coming. The Panchayat wants motorboats in only one lake. The other lake will be saved for the birds to make their nests.
- Find the area of lake B on the drawing in square cm. What is its actual area in square km?
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उत्तर
Lake B has 15 fully filled squares and 11 half-filled or more than half-filled squares.
- Area of 15 fully filled squares
= 15 × 15
= 225 square cm
We consider the area of every single half-filled or more than half-filled square as 1-centimetre square.
- Thus, the area of 11 such squares
= 11 × 11
= 121 square cm - So, the total area of lake B
= 225 + 121
= 346 square cm
We are given 1 cm on drawing = 1 km on the ground
Therefore, 346 square cm on drawing = 346 km
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संबंधित प्रश्न
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Write true or false.
Every measurement involves two things – a number and a unit.
Answer the following question.
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Solve the numerical example.
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| 1. | Length of the fore arm | metre |
| 2. | SI unit of length | second |
| 3. | Nano | 103 |
| 4. | SI Unit of time | 10–9 |
| 5. | Kilo | Cubit |
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Reason (R): The distance travelled by the light in one year is one light year.
Now guess the length and width of many other things. Measure and find the difference between your measure and your guess.
| Size of | Your guess in cm | Your measure in cm | ||
| Length | Width | Length | Width | |
| 100 Rupee note | ||||
| 10 Rupee note | ||||
| 20 Rupee note | ||||
| 5 Rupee note | ||||
| Post card | ||||
| Math-Magic book | ||||
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