Calculate Time to Complete a Work

To calculate time to complete a work in general if a person A completes 1/n th part of work in one day, then the time taken by A to complete the work = n days.

If a man takes 10 days to complete a piece of work; then according to the unitary method work done in a 1 day = 1/10. On the other hand, if a man completes 1/10th of the work in one day, to complete the work he will takes 10 days.


Now we will apply the concept of solving some real-life problems to find the time required to complete a piece of work.


Solved examples to calculate time to complete a work:

1. David can do a piece of work in 2 days while Ron can do the same work in 5 days. How long will it take if both of them work together?

Solution:

Time taken by David to do the work = 2 days

Work done by David in 1 day = 1/2

Time taken by Ron to do the work = 5 days

Work done by Ron in 1 day = 1/5

So, work by David and Ron in one day = 1/2 + 1/5

                                                        = (5 + 2)/10

                                                        = 7/10

Therefore, David and Ron can do a piece of work in 10/7 days, i.e., 1 3/7 days.


2. X can do a piece of work in 15 days while Y can do it in 30 days. If both of them at it together, in how many days will they be able to finish the work?

Solution:

Time taken by X to do a piece of work = 15 days

X’s one day’s work = 1/15 days

Time taken by Y to do a piece of work = 30 days

Y‘s one day’s work = 1/30 days

(X + Y)‘s one day’s work = 1/15 + 1/30

                                     = (2 + 1)/30

                                     = 3/30

                                     = 1/10

Therefore, both of them can finish the work in 10 days.


3. Harry and Sam can together plough the field in 5 days. Harry alone takes 8 days to plough the same field. In how many days can Sam alone plough the field?

Solution:

Time taken by Harry and Sam to plough the field together = 5 days

Therefore, Harry’s and Sam’s one day’s work = 1/5

Time taken by Harry to plough the field = 8 days.

Therefore, Harry’s one day’s work = 1/8

Therefore, Sam’s one day’s work = 1/5 – 1/8

                                                = (8 – 5)/40

                                                = 3/40

Therefore, Sam can plough the field in 3/40 days.


4. Aaron and Brandon can together do pieces of work in 15 days. Aaron alone can finish it in 20 days. How many days will Brandon take to finish the same work?

Solution:

(Aaron + Brandon)’s one day’s work = 1/15        

Aaron’s one day’s work = 1/20                                                                        

Therefore, Brandon’s one day’s work = (Aaron + Brandon)’s one day work – Aaron’s one day work

                                                      = 1/15 – 1/20

                                                      = (4 – 3)/60

                                                      = 1/60

Brandon alone can finish the work in 60 days.

Calculate Time to Complete a Work

Calculate Work Done in a Given Time

Problems on Time required to Complete a Piece a Work

Problems on Work Done in a Given Period of Time

Problems on Time and Work

Pipes and Water Tank

Problems on Pipes and Water Tank





7th Grade Math Problems

From Calculate Time to Complete a Work 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. How to Do Long Division? | Method | Steps | Examples | Worksheets |Ans

    Apr 20, 25 11:46 AM

    Long Division and Short Division Forms
    As we know that the division is to distribute a given value or quantity into groups having equal values. In long division, values at the individual place (Thousands, Hundreds, Tens, Ones) are dividend…

    Read More

  2. Word Problems on Division | Examples on Word Problems on Division

    Apr 20, 25 11:17 AM

    Word Problem on Division
    Word problems on division for fourth grade students are solved here step by step. Consider the following examples on word problems involving division: 1. $5,876 are distributed equally among 26 men. H…

    Read More

  3. Subtraction of 4-Digit Numbers | Subtract Numbers with Four Digit

    Apr 20, 25 10:27 AM

    Properties of Subtraction of 4-Digit Numbers
    We will learn about the subtraction of 4-digit numbers (without borrowing and with borrowing). We know when one number is subtracted from another number the result obtained is called the difference.

    Read More

  4. Subtraction without Regrouping |4-Digit, 5-Digit & 6-Digit Subtraction

    Apr 20, 25 10:25 AM

    Subtraction without Regrouping
    We will learn subtracting 4-digit, 5-digit and 6-digit numbers without regrouping. We first arrange the numbers one below the other in place value columns and then subtract the digits under each colum…

    Read More

  5. Worksheets on Missing Numbers from 1 to 20 | Counting Missing Numbers

    Apr 20, 25 10:17 AM

    Printable worksheets on missing numbers
    Printable worksheets on missing numbers from 1 to 20 help the kids to practice counting of the numbers.

    Read More

Worksheet on Work Done in a Given Period of Time

Worksheet on Time Required to Complete a Piece of Work

Worksheet on Pipes and Water Tank