Math, asked by nightread, 3 months ago

Answer the following questions:

Q.1 The distance between two stations is 500 km. A train takes 4 hours to cover this distance. Calculate the speed of the train.

Q.2 Rhea takes 20 minutes from her house to reach her school on a bicycle. If the bicycle has a speed of 2 ms-1. Calculate the distance between her house and the school.

Q.3 A simple pendulum takes 5s to complete 20 oscillations. What is the time period of the pendulum?

Q.4 A train is running at speed of 50 km/hr. How long will it take to cover a distance of 250 km?

Q.5 How much distance is travelled by an object if it travels at a constant speed of 60 Km/h for 2 hrs?

Q.6 Find the speed of an object which has travelled 3600m in one minute.

Q.7 A horse runs a distance of 200m in 10 seconds. What is the speed of horse in:-
i) Metre per second
ii) Kilometer per hour

Q.8 The Rajdhani Express travels at a speed of 80 Kmph. The distance between Delhi and Chennai is 2200Km. If it starts from Delhi at 3:00 PM, what time does it reach Chennai?

Please give full explanation.


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Answers

Answered by Sweetoldsoul
7

Answer:

Q1.

The distance between 2 stations (d) = 500km

time taken by train to cover 500km (t) = 4 hrs

speed of the train = d/ t

= 500/ 4

= 125  km/ h

                                                                                                                             

Q2.

speed of Rhea on bicycle (v) = 2 m/ s

time taken by Rhea to reach her house from school (t) = 20 mins

=> 1 minute = 60s

=> 20 minutes = 60 x 20

=> 1200 s

Distance between her school and her house = v x t

= 2 x 1200

= 2400 m

= 2.4 km (∵ 1000 m = 1km)

                                                                                                                             

Q3.

time taken for 20 oscillations (t) = 5 s

We know that, Time period of a simple pendulum is the time taken by the pendulum to complete One oscillation

=> time taken for 20 oscillations = 5s

=> time taken for 1 oscillation = 5/ 20 s

= 1/ 4 s

= 0.25 s

                                                                                                                             

Q4.

The speed of the train (v) = 50 km/ h

Distance to be travelled by the train (d) = 250 km

time taken to cover the distance (t) = d/ v

=> 250/ 50

= 5h

                                                                                                                             

Q5.

Speed of the object = 60km/ h

Time taken (t) = 2 hrs.

distance travelled by the object (d) = v x t

=> 60 x 2

=120 km

                                                                                                                             

Q6.

Distance travelled (d) = 3600m

Time taken (t) = 1 min

=> 1 min = 60s

speed of the object = d/ t

= 3600/ 60

= 60 m/ s

                                                                                                                             

Q7.

Distance run by a horse (d) = 200m

time taken (t) = 10s

(i) speed of the horse in m/ s (v)= d/ t

= 200/ 10

= 20m/ s

(ii) speed in km/ h = v x 18/ 5

=> 20 x 18/ 5

=> 18 x 4

= 72 km/ h

                                                                                                                             

Q8.

[The train starts from Delhi at 3:00 PM]

Speed of The Rajdhani Express (v) = 80 km/ h

Distance travelled (d) = 2200 km

Time taken by the train to reach Chennai (t) = d/ v

=> 2200/ 80

=> 55/ 2hr

=> 27\frac{1}{2} hr

=> 27hr + 1/ 2hr

=> 27hr + 30 mins

=> 24hr + 3hr + 30 mins

(24 hrs = 1 day... if the train starts at 3 pm today then after 24 hrs it would have have reached a destination at 3 pm of the next day)

=> 3 PM + 3hr + 30 mins

= 6 PM 30 mins

= 6 : 30 PM (of next day)

Answered by EmeliaAdair
2

Answer:

Let the CP of each pen be Rs.x.

Then,

CP of 12 pens=Rs.12

SP of 12 pens=CP of 15 pnes=Rs.15

now,gain=SP-CP=Rs.(15-12)=Rs.3

gain%=gain/cp*100

=(3/12*100)%=25%

Hence,the gain=25%.

By: arishta jain, 8 years ago3 like this answer

Let the C.P of 1 pen be Rs.1

Therefore,

The C.P of 15 pens = Rs. 15

Given,

C.P of 15 pens= S.P of 12 pens.

So, S.P of 12 pens = Rs.15

Selling Price of 1 pen = Rs. 1.25

Gain= Rs. 0.25

Gain percent= Gain x 100/C.P %

= 0.25 x 100/1 %

=25/1 %

= 25 %

Therefore, the gain percent is 25%

Hope You understood it... :-)

Step-by-step explanation:

there's a other method!or sum...

SP OF 12 PENS =CP OF 15 PENS

SP OF 1 PENS = R. 1

SP OF 12 PENS= R. 12

SP OF 15 PENS = R. 15

CP OF 15 PENS =R. 12

NOW, SP >CP

SO, GAIN = SP -CP

=R. 15 - R. 12 =R. 3

GAIN % = GAIN *100. =3/12 *100 =25%

CP

Answer=25%

this is the answer to the last question u asked!.

I'm not sure if I got it right! but hope it helped!

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