Find the best solutions to your questions at Westonci.ca, the premier Q&A platform with a community of knowledgeable experts. Explore a wealth of knowledge from professionals across different disciplines on our comprehensive platform. Join our Q&A platform to connect with experts dedicated to providing accurate answers to your questions in various fields.

Cora is revising for two subjects, History and French. The time she spends revising is in the ratio:

History : French = 7 : 2

The time she spends revising for History is 20 hours more than for French.

Work out the total time she spends revising.


Sagot :

Certainly! Let's break down the problem step by step.

First, let [tex]\( x \)[/tex] represent the time Cora spends revising for French in hours.

Given the ratio of the time spent on History to French is [tex]\( 7:2 \)[/tex], the time she spends on History can be expressed in terms of [tex]\( x \)[/tex]:
[tex]\[ \text{Time spent on History} = \frac{7}{2}x \][/tex]

We also know that the time spent on History is 20 hours more than the time spent on French:
[tex]\[ \frac{7}{2}x = x + 20 \][/tex]

To solve for [tex]\( x \)[/tex], we can set up the equation:
[tex]\[ \frac{7}{2}x = x + 20 \][/tex]

Next, we need to clear the fraction by multiplying every term by 2:
[tex]\[ 7x = 2x + 40 \][/tex]

Now, we isolate [tex]\( x \)[/tex] by subtracting [tex]\( 2x \)[/tex] from both sides of the equation:
[tex]\[ 5x = 40 \][/tex]

Then, we solve for [tex]\( x \)[/tex] by dividing both sides by 5:
[tex]\[ x = \frac{40}{5} \][/tex]
[tex]\[ x = 8 \][/tex]

So, Cora spends 8 hours revising for French.

Now, we find the time Cora spends revising for History:
[tex]\[ \text{Time spent on History} = x + 20 = 8 + 20 = 28 \text{ hours} \][/tex]

Finally, we calculate the total time Cora spends revising for both subjects:
[tex]\[ \text{Total time} = \text{Time spent on French} + \text{Time spent on History} \][/tex]
[tex]\[ \text{Total time} = 8 + 28 = 36 \text{ hours} \][/tex]

Therefore, the total time Cora spends revising is 36 hours.