Answer:
c
Step-by-step explanation:
6x+42+3x
6x+3x +42
9x+ 42
Answer:
Dave will make $200 for the sales of $1000.
Step-by-step explanation:
Given are:
Rate of commission of Dave = 20%
Total sales = $1000
The amount that Dave will make will be obtained by calculating the 20% of total sales.
For that we will multiply the sales with 0.20

Hence,
Dave will make $200 for the sales of $1000.
Answer:
$18
Step-by-step explanation:
$15 for meal
15% for tip = $2.25
5% sales tax = $0.75
Total cost of eating $18
Answer:
40
Step-by-step explanation:
1) the basic is: the mass of the salt before pure water is added = the mass of the salt after the pure water is added;
2) the mass of the salt before pure water is added was:
40*0.1;
3) the mass of the salt after pure water is added is:
(40+w)*0.05, where w - the required mass of pure water;
4) if the mass of the salt is the same, then:
40*0.1=(40+w)*0.05;
5) if to evaluate the equation:
(w+40)*0.05=4; ⇔ w+40=80; ⇔ w=40 gr.