She washed 30 plates from 7:30 to 7:35.....so she washed 30 plates in 5 minutes.....30/5 = 6 plates per minute
so if she started washing plates at 7:15 and ended at 7:38...how many plates did she wash....
from 7:15 to 7:38 is 23 minutes...and if she can wash 6 plates per minute, then in 23 minutes, she can wash (23 * 6) = 138 plates <==
the equation...
y = -6x + b...with b being the number of plates she started with and x being the number of minutes and y being the plates she has left to wash...I am not 100% sure on this equation...I am so sorry
W = 6
b = 4
You have a 3/5 chance every time to pull a white marble.
35 x 0.6 (6/10) = 21.
Your answer is D.)
<em><u>It's 30</u></em>
<em>Hope that helped!</em>