Answer:
$150
Step-by-step explanation:
A tip would be 20% of the cost. So 30 is 20% of the cost. Let's find the total cost.
Use the percent proportion: percent/100 = part/whole.
20/100 = 30/x
20x=3000
Divide each side by 20 to isolate the variable.
3000/20= 150
So 150 is our total cost. Now we need to subtract 30 from that.
150-30=120.
So our food and drinks bill would be $150.
Double check:
20/100=30/150
Simplify down to
1/5=1/5
So yes, it is correct.