If the dresses are chosen at random a probability tree can be constructed showing the probabilities of the various combinations that are possible. It shows the total probability of choosing a black, then white, or a white, then black dress is 1/9.
The fraction is 
Step-by-step explanation:
Let,
The denominator of fraction = x
Numerator of fraction = x-3
Fraction = 
According to given statement;
1 is added to the numerator, the value of the fraction becomes 3/4.

Using cross multiplication

Fraction = 
Keywords: fraction, division
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Answer:
5 is the mean
Step-by-step explanation:
Answer:
P=2(l+w)
divide the both sides by 2
P/2 = l +w
make w the subject of the formula
P/2 - l =w
w = P/2 - l
Student b? could you send a full picture