We are asked to solve several mathematical problems: 7. Write $5 \times 10000 + 2 \times 100 + 3 \times 10 + 8$ in its simplest form. 8. How many days from 25th December 2013 to 25th February 2014? 9. If it takes Sofia 40 seconds to run around a yard, how many complete laps could she run in 5 minutes? 10. What time is it 300 minutes after 9:25 am? 11. Petrol costs $22 for 20 litres. How much would 1 litre of petrol cost? 12. I am thinking of two numbers whose product is 30 and whose sum is 11. What are the two numbers?

1. Problem Description

We are asked to solve several mathematical problems:

7. Write $5 \times 10000 + 2 \times 100 + 3 \times 10 + 8$ in its simplest form.

8. How many days from 25th December 2013 to 25th February 2014?

9. If it takes Sofia 40 seconds to run around a yard, how many complete laps could she run in 5 minutes?

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0. What time is it 300 minutes after 9:25 am?

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1. Petrol costs $22 for 20 litres. How much would 1 litre of petrol cost?

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2. I am thinking of two numbers whose product is 30 and whose sum is

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1. What are the two numbers?

2. Solution Steps

7. We need to evaluate the expression $5 \times 10000 + 2 \times 100 + 3 \times 10 + 8$.

$5 \times 10000 = 50000$

$2 \times 100 = 200$

$3 \times 10 = 30$

Therefore, $50000 + 200 + 30 + 8 = 50238$.

8. Number of days from 25th December 2013 to 25th February 2014:

Days in December (from 25th to 31st): $31 - 25 + 1 = 7$ days.

Days in January 2014: 31 days.

Days in February 2014 (from 1st to 25th): 25 days.

Total days: $7 + 31 + 25 = 63$ days.

9. If Sofia takes 40 seconds to run one lap, we need to find how many laps she can run in 5 minutes.

First, convert 5 minutes to seconds: $5 \times 60 = 300$ seconds.

Then, divide the total time in seconds by the time per lap: $\frac{300}{40} = 7.5$.

Since we need complete laps, Sofia can run 7 complete laps.

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0. We need to find the time 300 minutes after 9:25 am.

First, convert 300 minutes to hours: $\frac{300}{60} = 5$ hours.

Then, add 5 hours to 9:25 am: 9:25 am + 5 hours = 2:25 pm.

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1. If petrol costs $22 for 20 litres, we need to find the cost of 1 litre.

Divide the total cost by the number of litres: $\frac{22}{20} = 1.1$.

Therefore, 1 litre of petrol costs $1.

1.

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2. We are looking for two numbers such that their product is 30 and their sum is

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1. Let the two numbers be $x$ and $y$.

$x \times y = 30$

$x + y = 11$

We can express $y$ as $y = 11 - x$.

Substitute into the first equation: $x \times (11 - x) = 30$

$11x - x^2 = 30$

$x^2 - 11x + 30 = 0$

$(x - 5)(x - 6) = 0$

So, $x = 5$ or $x = 6$.

If $x = 5$, then $y = 11 - 5 = 6$.

If $x = 6$, then $y = 11 - 6 = 5$.

The two numbers are 5 and

6.

3. Final Answer

7. 50238

8. 63 days

9. 7 laps

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0. 2:25 pm

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1. $1.1

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2. 5 and 6