John and Smith went to a stationery shop.

John bought 6 pens, 4 pencils and 3 erasers. Smith bought 3 pens, 8 pencils and 6 erasers and spent 20% more than John. What percentage money did John spend on pens?

How can I form an equation and solve?

Let the cost of John's 4 pencils and 3 erasers be x

then the cost of Smith's 8 pencils and 6 erasers is 2x , notice twice as many

cost of Smiths 3 pens --- y
cost of John's 6 pens ---- 2y , notice twice as many pens

Johns cost = 2y + x
Smith's cost = y + 2x

y + 2x = 1.2(2y + x)
y + 2x = 2.4y + 1.2x
.8x = 1.4y
8x = 14y
4x = 7y
y = 4x/7

percentage that john spent on pens
= 2y/(2y+x)
=(8x/7)/(8x/7 + x)
= (8x/7)/(15x/7)
= (8x/7)(7/15x
= 8/15
= appr 53.3%

check my arithmetic

To solve this problem, let's first start by finding the total amount spent by both John and Smith. Given that Smith spent 20% more than John, we can assume that John spent x dollars. Therefore, Smith spent (x + 20% of x) = (x + 0.2x) = 1.2x dollars.

Next, we need to determine the amount of money John spent on pens. From the given information, we know that John bought 6 pens, 4 pencils, and 3 erasers. Assuming the cost of each item is equal, let the cost of each pen be y dollars.

John's total expenditure on pens can then be calculated as 6y dollars.

Now, we can set up an equation to find the value of y:

6y = x

Simplifying this equation, we can express x in terms of y:

x = 6y

Since we know that John spent x dollars on pens, we can substitute this value into the equation:

6y = 1.2x

Simplifying further, we get:

6y = 1.2(6y)

Now, let's solve for y:

6y = 7.2y
0.2y = 0
y = 0

This means that John didn't spend any money on pens.

Therefore, the percentage of money spent by John on pens is 0%.