Hi there!

First we need to work out the parenthesis, which can for instance be done using rainbow technique.

Now subtract 3 from both sides.

And finally add 3x to both sides.

The 4th answer choice is correct.
One pizza serves four people so, you will need 10 pizzas for 40 people so that make the answer (A.)
I would be able to but i left my maths book at school and that has the explanation in, sorry :(
The average of the 75 customers will be 6.4.
<h3>How to calculate the value?</h3>
The first 30 customers made an average of 5 claims each. The total claims will be:
= (5 × 30) = 150
When 75 more people were assessed, the average was 6. Therefore, the total claims will be:
= (75 + 30) × 6
= 105 × 6
= 630
Therefore, the average of the 75 customers will be:
= (630 - 150)/75
= 480/75
= 6.4
Learn more about mean on:
brainly.com/question/1136789
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