a) Let x, y, and z be the selling price of one cabbage, one orange, and one mango, respectively.
From the given data, we can write three simultaneous equations:
Monday: 55x + 100y + 95z = 1625
Tuesday: 60x + 120y + 80z = 1580
Wednesday: 75x + 150y + 120z = 2175
b) To find the selling price of each item, we need to solve the system of equations. We can use any method of solving systems of equations, such as substitution or elimination. Here, we will use the elimination method.
Multiplying the first equation by 6, the second equation by -5, and the third equation by 3, we get:
Monday: 330x + 600y + 570z = 9750
Tuesday: -300x - 600y - 400z = -7900
Wednesday: 225x + 450y + 360z = 6525
Adding all three equations, we get:
255x + 450y + 530z = 8385
Dividing both sides by 5, we get:
51x + 90y + 106z = 1677
Now we can use this equation and any of the original equations to solve for one of the variables. Let's use the first equation:
55x + 100y + 95z = 1625
Multiplying both sides by 106 and subtracting 530 times the first equation from it, we get:
76x + 45z = 43
Solving for x, we get:
x = (43 - 45z)/76
Now we can substitute this value of x into any of the previous equations to solve for y and z. Let's use the third equation:
75x + 150y + 120z = 2175
Substituting x, we get:
75[(43-45z)/76] + 150y + 120z = 2175
Simplifying, we get:
43z/2 - 375/2 + 150y = 825
Solving for y, we get:
y = (825 - 43z/2 + 375/2)/150
Now we can substitute the values of x and y into any of the previous equations to solve for z. Let's use the second equation:
60x + 120y + 80z = 1580
Substituting x and y, we get:
60[(43-45z)/76] + 120[(825-43z/2+375/2)/150] + 80z = 1580
Simplifying, we get:
z = 4.6
Substituting z into the equation for y, we get:
y = 3.45
Substituting z and y into the equation for x, we get:
x = 1.5
Therefore, the selling price for one cabbage is sh. 1.5, for one orange is sh. 3.45, and for one mango is sh. 4.6.
c) The profit that James Kamau made on each of the three days and his total profits:
To calculate the profit, we need to subtract the cost of the items from the revenue generated by selling them.
On Monday:
Cost of cabbages = 55 x 3 = 165 shillings
Cost of oranges = 100 x 2 = 200 shillings
Cost of mangoes = 95 x 6 = 570 shillings
Total cost = 935 shillings
Revenue = 1625 shillings
Profit = Revenue - Cost = 1625 - 935 = 690 shillings
On Tuesday:
Cost of cabbages = 60 x 3 = 180 shillings
Cost of oranges = 120 x 2 = 240 shillings
Cost of mangoes = 80 x 6 = 480 shillings
Total cost = 900 shillings
Revenue = 1580 shillings
Profit = Revenue - Cost = 1580 - 900 = 680 shillings
On Wednesday:
Cost of cabbages = 75 x 3 = 225 shillings
Cost of oranges = 150 x 2 = 300 shillings
Cost of mangoes = 120 x 6 = 720 shillings
Total cost = 1245 shillings
Revenue = 2175 shillings
Profit = Revenue - Cost = 2175 - 1245 = 930 shillings
Total profit over three days:
Profit on Monday + Profit on Tuesday + Profit on Wednesday = 690 + 680 + 930 = 2300 shillings
Therefore, James Kamau made a profit of 690 shillings on Monday, 680 shillings on Tuesday and 930 shillings on Wednesday, with a total profit of 2300 shillings over the three days.