Question

A man travelled from the village to the post office at the rate of 25kmph and walked back at the rate of 4kmph.If the whole journey took 5hours48 minutes, then the distance of the post office from the village is
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Answer 1

Answer:

Step-by-step explanation:

Given: p = 4, α = 15° The equation of the line in normal form is given by We know that, cos 15° = cos (45° – 30°) = cos45°cos30° + sin45°sin30° Cos (A – B) = cos A cos B + sin A sin B So, And sin 15 = sin (45° – 30°) = sin 45° cos 30° – cos 45° sin 30° Sin (A – B) = sin A cos B – cos A sin B So, Now, by using the formula, x cos α + y sin α = p Read more on Sarthaks.com - https://www.sarthaks.com/804281/find-the-equation-of-the-line-whose-perpendicular-distance-from-the-origin-is-4-units

Now, substitute the values, we get (√3 + 1)x +(√3 - 1) y = 8√2 ∴ The equation of line in normal form is (√3 + 1)x +(√3 - 1) y = 8√2. Read more on Sarthaks.com - https://www.sarthaks.com/804281/find-the-equation-of-the-line-whose-perpendicular-distance-from-the-origin-is-4-units

Answer 2

★Given:-

• A man travelled from the village to the post office at the rate of 25kmph.
• Walked back at the rate of 4kmph.
• Time taken for the whole journey = 5hours 48 minutes.

★To find:-

• The distance of the post office from the village.

★Solution:-

Using the formula,

✦Time = Distance/Speed

Putting values,

Time taken to travel to the post office is,

➜Time = Distance/25  

Time taken in going back to the village is,

➜Time = Distance /4

 Given that the total time taken is 5 hours 48 mins.

And,

5 hours 48 min = 5 4/5 hour

                        =29/5 hrs

According to question,

➜x/25 + x/4 = 29/5

➜29/100 x= 29/5

➜x = (29/5) ÷ (29/100)

➜x = 20km

Therefore,

The distance of the post office from the village is 20km.

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