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#1 2018-07-01 04:58:54

Zeeshan 01
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Registered: 2016-07-22
Posts: 746

Question

If Ali can finish a job in 5 hours and Hashim can finish the same job in 10 hours , how many minutes will it take both of them together to finish the job?


Malik

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#2 2018-07-01 05:01:51

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 746

Re: Question

Question 2 : Successive discounts of 10% and 15% is equivalent to a single discount of

Options
A:24%
B:24.5%
C:23.5%
D:22%
E:25%


Malik

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#3 2018-07-01 06:00:34

Bob
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Registered: 2010-06-20
Posts: 10,053

Re: Question

Here again you can use x.

Let the amount of work to be done be x.

Then Ali works at x/5 work units per hour and Hashim at x/10.  Add these to get their combined work rate and use the formula:

 

If the price is  x then a discount of 10% means it will now cost 0.9x and then multiply by a further 0.85 to apply the second discount.

If this is kx then the discount is (x-kx)/x times 100%

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#4 2018-07-01 17:02:47

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 746

Re: Question

bob bundy wrote:

Then Ali works at x/5 work units per hour and Hashim at x/10.  Add these to get their combined work rate and use the formula:
Bob

Adding this lead to (3*x)/10


Malik

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#5 2018-07-01 17:18:25

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 746

Re: Question

combined rate of working = (3*x)/10  *   50

then answer is 15x


Malik

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#6 2018-07-01 17:20:11

Zeeshan 01
Member
Registered: 2016-07-22
Posts: 746

Re: Question

bob bundy wrote:

If the price is  x then a discount of 10% means it will now cost 0.9x and then multiply by a further 0.85 to apply the second discount.

Bob

If the discount is 10% then how it costs 0.9x?


Malik

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#7 2018-07-01 18:38:37

Bob
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Registered: 2010-06-20
Posts: 10,053

Re: Question

If the discount is 10% then how it costs 0.9x?

If you take 10% off the price, you'll be left with 90% to pay.

3x/10 is correct.  Then rearrange the formula I gave:

This answer will be in hours so you'll need to convert to minutes.

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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