One book that Josh owns had a value of £15 on the 1st May 2019
The value of this book had increased by 20% in the last year.
(b) Find the value of the book on the 1st May 2018



Answer :

To determine the value of the book on the 1st May 2018, given its value on the 1st May 2019 was £15 and it increased by 20% over the year, follow these steps:

1. Let's denote the value of the book on the 1st May 2018 as [tex]\( V_{2018} \)[/tex].

2. We know that the value of the book increased by 20%. This means that the value of the book on the 1st May 2019, which is £15, is 120% of its value on the 1st May 2018.

3. To express this relationship mathematically:
[tex]\[ V_{2019} = V_{2018} \times 1.20 \][/tex]

Given that [tex]\( V_{2019} \)[/tex] is £15:
[tex]\[ 15 = V_{2018} \times 1.20 \][/tex]

4. To find [tex]\( V_{2018} \)[/tex], we need to isolate it by dividing both sides of the equation by 1.20:
[tex]\[ V_{2018} = \frac{15}{1.20} \][/tex]

5. Performing the division:
[tex]\[ V_{2018} = \frac{15}{1.20} = 12.5 \][/tex]

Thus, the value of the book on the 1st May 2018 was £12.5 (or £12.50).

Answer:

12.5

Step-by-step explanation:

To find the value of the book on the 1st of May, 2018 we can make a formula:

[tex]l \times 1.2 = n[/tex]

Where:

  • l means last year's value
  • n means next year's value = 15
  • 1.2 is represented by adding 20% (0.2) to the last year's value

Making l the subject of formula:

[tex]l \times 1.2 = n\\\\l = \frac{n}{1.2}[/tex]

l = 15/1.2

l = 12.5

Therefore, the value of the book last year (1st May, 2018) simplifies to:
[tex]\boxed{\boxed{12.5}}[/tex]