Terri can swim 3 laps in 2.5 minutes. To find how long it takes to swim 20 laps, you can make a proportion.
Put the amount of laps on the top and the time(minutes) at the bottom.
Cross multiply:
Divide by 3:
It would take Terri 
OR 
minutes to run 20 laps.
The answer is D: to dilate the triangle by a scale factor of 1:2 (or 1/2).
I hope this Helps!
Answer:
$2.40 for the video game and $14.8 for the DVDs
Step-by-step explanation:
1 video game = $2.40
4 DVDs = $14.8
$3.70 x 4 = $14.8
B = 3h . . . . . . . .given by the problem statement
A = (1/2)bh . . . . formula for the area of a triangle
486 cm² = (1/2)*(3h)*h . . . substitute given information
(2/3)*486 cm² = h² . . . . . .multiply by 2/3
√324 cm = h . . . . . . . . . . . . . .take the square root
The height is 18 cm.
The base is 3*18 = 54 cm.
