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**Zeeshan 01****Member**- Registered: 2016-07-22
- Posts: 673

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?

MZk

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**Zeeshan 01****Member**- Registered: 2016-07-22
- Posts: 673

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%

MZk

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**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,371

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

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**Zeeshan 01****Member**- Registered: 2016-07-22
- Posts: 673

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

MZk

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**Zeeshan 01****Member**- Registered: 2016-07-22
- Posts: 673

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

then answer is 15x

MZk

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**Zeeshan 01****Member**- Registered: 2016-07-22
- Posts: 673

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?

MZk

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**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,371

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

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