So, the first thing you want to find out is how many seconds each person adds to the wait time. Find out how many seconds are in 20 minutes.. 20*60=120. 120/150=0.8 seconds. Each person adds 0.8 seconds to the wait time. Now, multiply that by 240.. 240*0.8=192 seconds. Lastly, find out how many minutes 192 seconds is... 192/60=32 minutes.
I hope I did that right! And if I did, I hope that helped!
Answer:
Step-by-step explanation:
The ratio of corresponding sides DN and KI is 12 : 4 = 3 : 1. The same ratio applies to altitudes DQ and KO. Since the difference between these altitudes is 6 and the difference between their ratio units is 3-1 = 2, each ratio unit must stand for 6/2 = 3 units of linear measure. That is, ...
DQ = (3 units)·3 = 9 units
KO = (3 units)·1 = 3 units
Then the base lengths QN and OI can be found from the Pythagorean theorem:
KI² = KO² +OI²
4² = 3² +OI²
OI = √(16 -9)
OI = √7
QN = 3·OI = 3√7
System of equations:
We'll need one equation for the amount of pizzas, and another for the total cost of the pizzas. In this case, x will represent small pizzas, and y will represent large pizzas.
3x + 4y = 100
x + y = 30
Solving the system of equations:
First, we need to solve for one variable in one equation.
x + y = 30
x = 30 - y
Then, we'll take our equation that is solved for x and plug it into the other equation from above.
3(30 - y) + 4y = 100
Next, we solve for y.
90 - 3y + 4y = 100
90 + y = 100
y = 10
Finally, we take our value for y and plug it back in to the very first equation and solve for x.
x = 30 - 10
x = 20
Answer:
The student has sold 10 large pizzas and 20 small pizzas.
Hope this helps!! :)