A bag contains n counters.
One counter is blue and the rest are red.
Two counters are taken at random from the bag.
a) Express, in terms of n, the probability that a counter of each colour is
Give your answer as a fraction in its simplest form.
b) The probability that a counter of each colour is taken is 0.125
How many red counters are in the bag?

Blue

1 / n

Red

n-1 / n = 1 - 1 / n

7 red containers

Step-by-step explanation:

If there are "n" counters in total but we know that one is blue it means that there are "n - 1" red counters, which means that the probability for when one of them is:

Blue

1 / n

Red

n-1 / n = 1 - 1 / n

for part b, we have that the probability is 0.125, that is:

1 / n = 0.125

if we solve for n:

n = 1 / 0.125

n = 8

knowing that of the 8 one is blue, it means that the rest are red, that is to say that there are 7 (8 - 1) red containers

so firstly, we need to isolate the y variables to be able to solve these inequalities. firstly, add 0.5x on both sides of the first inequality and subtract 1.5x on both sides of the second inequality:

now since the slope is positive for the first inequality, this means that the line going upwards belongs to the first inequality, and the line going downwards belongs to the second inequality.

next, since y ≥ in the first inequality, this means that the shaded region will be above the first inequality's line, thus shading regions a and b.

next, since y ≤ in the second inequality, this means that the shaded region is going to be below this line, thus shading regions a and c.

since both lines shade region a, this means that region a is the solution.

step-by-step explanation:

mark brainliest!