Question 1201920
x = number of kilograms of type 1 tea costing 140 shillings per kilogram.
y = number of kilograms of type 2 tea costing 160 shillings per kilogram.
the current ratio is 2 kilograms of type 1 for every 3 kilograms of type 2.
this tells you that, for every 5 kilograms, 2 of them are type 1 and 3 of them are type 2.
the ratio of type 1 to total mass is 2/5 and the ratio of type 2 to total mass is 3/5.
if the total mass is 1 kilogram, then type 1 = 2/5 kilograms and type 2 = 3/5 kilograms.
total cost is 2/5 * 140 + 3/5 * 160 = 152 per kilogram.
revenue is 240 per kilogram.
profit is 240 - 152 = 88 per kilogram.
percent profit is 88 / 152 * 100 = 57.89473684%.
round to two decimal places to get 57.89%.
to get a mix that costs 148 shillings per kilogram, solve the following two equations simultaneously.
x + y = 1
140 * x + 160 * y = 148
multiply both sides of the first equation by 140 and leave the second equation as is to get:
140 * x + 140 * y = 140
140 * x + 160 * y = 148
subtract the first equation from the second to get:
20 * y = 8
solve for y to get:
y = 8 / 20 = .4
since x + y = 1, x must be equal to .6
your cost per kilogram of the mix is now:
.6 * 140 + .4 * 160 = 148.
note that .6 = 3/5 and .4 = 2/5.
your original mix was 2/5 * 140 + 3/5 * 160 = 152 per kilogram.
your new mix is 3/5 * 140 + 2/5 * 160 = 148 per kilogram.
the original ratio was x/y = 2/3.
the new mix is x/y = (3/5) / (2/5) = 3/5 * 5/2 = 3/2.
you went from an x/y ratio of 2/3 to an x/y ratio of 3/2.