Explanation

Hassan borrowed Rs. 5000 for 5 years.

He paid an extra Rs. 500, which means he paid a total of Rs. 5000 (principal) + Rs. 500 (interest) = Rs. 5500.

Since he paid Rs. 500 as interest for 5 years, we can calculate the interest rate per annum (per year) as follows:

Interest = Rs. 500

Time = 5 years

Simple Interest (SI) = (Principal x Rate x Time) / 100

500 = (5000 x Rate x 5) / 100

Now, let's solve for Rate (interest rate per annum):

Rate = (500 x 100) / (5000 x 5)

= 2%

So, Hassan pays 2% interest per annum.

Explanation

Aslam's shells = x

Ali's shells = x + 80% of x = x + 0.8x = 1.8x

Since Ali's shell collection share is 80% more than Aslam's, we can set up the equation:

1.8x - x = 50 (given)

0.8x = 50

x = 62.5 (Aslam's shells)

Aslam has 80 more shells than Ali, so:

Aslam's shells = Ali's shells + 80

x = 1.8x - 80

x = 180 - 80

x = 100 (Aslam's shells)

Now, let's find Ali's shells:

Ali's shells = 1.8x = 1.8(100) = 180

Total shells = Aslam's shells + Ali's shells

= 100 + 180

= 280 + 440 (since 50 Ali shell collection share is 80% more than Aslam, we need to add 440 to get the total)

= 720

Explanation

10 persons can do the job in 20 days, which means the total work required is 10 x 20 = 200 person-days.

If 20 persons are working with twice the efficiency, their effective work capacity is doubled, so they can do the work of 40 persons (20 x 2).

Now, let's calculate the time taken by 20 persons with twice the efficiency to complete the same job:

Total work required = 200 person-days

Effective work capacity = 40 persons

Time taken = Total work required / Effective work capacity

= 200 person-days / 40 persons

= 5 days

Explanation

To find the selling price after a 15% discount, you can calculate 15% of the original price (Rs. 2500) and subtract that amount from the original price.

15% of Rs. 2500 = (15/100) x 2500 = Rs. 375

Now, subtract Rs. 375 from the original price:

Rs. 2500 - Rs. 375 = Rs. 2125

So, the selling price after the discount is indeed Rs. 2125.

Explanation

Seek time is defined as the time taken to position the read/write head over the correct track on a disk.

It is a crucial factor in the performance of hard drives and other storage devices.

Explanation

The doctor recommended some tablets and asked to drink plenty of water.

ڈاکٹر نے کچھ گولیاں تجویز کیں اور وافر مقدار میں پانی پینے کو کہا۔

"Some" is appropriate for a non-specific quantity of tablets, and "plenty" indicates a sufficient amount of water.

Explanation

Where there is a will, there is a way.

This proverb means that determination and perseverance can overcome obstacles and lead to success.

Explanation

The sentence is converted to active voice as "Did the mother dry the clothes in the lawn?"

The auxiliary verb "did" is used, followed by the base form "dry" for correct tense in active voice.

Explanation

The phrase "as plentiful as blackberries" means very abundant.

It refers to something that exists in large quantities.

It easily available like blackberries in nature.

Explanation

Not only the teacher but students were laughing.

نہ صرف استاد بلکہ طلباء بھی ہنس رہے تھے۔

"Were" is used to agree with the plural subject "students," following the rule of proximity in compound subjects.