A girl buys x magazines at 50p each and x-3 magazines at 40p each. She spends £6 in all. Find x?
just add up the costs:
50x + 40(x-3) = 600
50x + 40x - 120 = 600
90x = 720
x = 8
0.5x + 0.4(x-3) = 6
0.5x + 0.4x - 1.2 = 6
0.9x = 7.2
x = 8
To find the value of x, we need to set up an equation based on the given information. Let's break it down step by step:
1. The girl buys x magazines at 50p each. This means the cost of x magazines is 50p * x, or 50x pence.
2. The girl also buys x-3 magazines at 40p each. So, the cost of x-3 magazines is 40p * (x-3), or 40(x-3) pence.
3. The total cost of all the magazines is given as £6. To convert this into pence, we multiply it by 100 since there are 100 pence in a pound. So, £6 equals 6 * 100 pence, which is 600 pence.
4. Now we can set up the equation: 50x + 40(x-3) = 600. This equation represents the total cost of all the magazines.
5. We can now solve the equation to find x. Let's simplify it:
50x + 40x - 120 = 600
90x - 120 = 600
90x = 720
x = 720 / 90
x = 8
Therefore, the value of x is 8.