Problems on Calculating Time

Here we will learn to solve different types of problems on calculating time.

We know, the formula to find out time = distance/speed


Word problems on calculating time:

1. A car travel 60 km in 30 minutes. In how much time will it cover 100 km?

Solution:            

Using the unitary method;

Time taken to cover 60 km = 90 minutes

Time taken to cover 1 km = 90/60 minutes

Time taken to cover 100 km = 90/60 × 100 = 150 minutes

Formula of speed = distance/time

= 60 km/(3/2) hr              [given 1 hour 30 min = 1 30/60 = 1 ½ hours

= 3/2 hours]

= 60/1 × 2/3 km/hr = 40 km/hr

Now, using the formula of time = distance/speed = 100 km/40 km/hr = 5/2 hours

= 5/2 × 60 minutes, (Since 1 hour = 60 minutes)

= 150 minutes


2. Victor covers 210 km by car at a speed of 70 km/hr. find the time taken to cover this distance.

Solution:            

Using the unitary method;

70 km is covered in 1 hour.

1 km is covered in 1/70 hours.

210 km is covered in 1/70 × 210 hours = 3 hours

Given: speed = 70 km/hr, distance covered = 210 km

Time taken = Distance/ Speed = 210/70 hours = 3 hours


3. A train covers a distance of 36 km in 15 minutes. Find the time taken by it to cover the same distance if its speed is decreased by 9 km/hr.

Solution:            

Distance covered by train = 36 km

Time taken = 15 minutes = 15/60 hr = ¼ hr.

Therefore speed of train = Distance covered/time taken

                                    = 36/(1/4) km/hr

                                    = 36/1 × 4/1

                                    = 144 km/hr

Reduced speed = 144 – 9 = 135

Therefore, required time = distance covered/speed

                                    = 36/135 × 60 minutes

                                    = 16 minutes


4. A man is walking at a speed of 6 km per hour. After every km, he takes rest for 2 minutes. How much time will it take to cover a distance of 4 km?

Solution:            

Rest time = Number of rests × time of each rest

               = 3 × 2 minutes

               = 6 minutes

Total time to cover 4 km = 4/6 × 60 + 6 minutes

                                     = (40 + 6) minutes

Speed of Train

Relationship between Speed, Distance and Time

Conversion of Units of Speed

Problems on Calculating Speed

Problems on Calculating Distance

Problems on Calculating Time

Two Objects Move in Same Direction

Two Objects Move in Opposite Direction

Train Passes a Moving Object in the Same Direction

Train Passes a Moving Object in the Opposite Direction

Train Passes through a Pole

Train Passes through a Bridge

Two Trains Passes in the Same Direction

Two Trains Passes in the Opposite Direction





8th Grade Math Practice

From Problems on Calculating Time to HOME PAGE




Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.



New! Comments

Have your say about what you just read! Leave me a comment in the box below. Ask a Question or Answer a Question.




Share this page: What’s this?

Recent Articles

  1. Worksheet on Comparing and Ordering Decimals |Arranging Decimals

    Apr 19, 25 12:16 PM

    Arranging Decimals
    Practice different types of math questions given in the worksheet on comparing and ordering decimals. This worksheet contains questions mainly related to compare decimals and then place the decimals i…

    Read More

  2. Comparison of Decimal Fractions | Comparing Decimals Numbers | Decimal

    Apr 19, 25 11:47 AM

    Comparison of Decimal Fractions
    While comparing natural numbers we first compare total number of digits in both the numbers and if they are equal then we compare the digit at the extreme left. If they also equal then we compare the…

    Read More

  3. Expanded form of Decimal Fractions |How to Write a Decimal in Expanded

    Apr 19, 25 11:25 AM

    Expanded form of Decimal
    Decimal numbers can be expressed in expanded form using the place-value chart. In expanded form of decimal fractions we will learn how to read and write the decimal numbers. Note: When a decimal is mi…

    Read More

  4. Missing Numbers up to 10 | Worksheets on Missing Numbers up to 10

    Apr 18, 25 04:53 PM

    missing numbers up to 10
    Printable worksheets on missing numbers up to 10 help the kids to practice counting of the numbers.

    Read More

  5. Ordering Decimals | Comparing Decimals | Ascending & Descending Order

    Apr 18, 25 01:49 PM

    Ordering Decimal Numbers
    In ordering decimals we will learn how to compare two or more decimals. (i) Convert each of them as like decimals. (ii) Compare these decimals just as we compare two whole numbers ignoring

    Read More

Worksheet on Conversion of Units of Speed

Worksheet on Calculating Time

Worksheet on Calculating Speed

Worksheet on Calculating Distance

Worksheet on Train Passes through a Pole

Worksheet on Train Passes through a Bridge 

Worksheet on Relative Speed

Worksheet on Decimal into Percentage