Add 7 to both sides
3x + 12 = 7x
Subtract 3x
12 = 4x
Divide by 4
x = 3
The sum of the interior angles of a triangle is 180. Add the three measures given and if you get 180 then those can be the interior angles of a triangle.
Work it exactly like the other one with Wilda and Karla.
Juan takes 15 hours to do a job ... he does 1/15 of it in an hour.
His father can do it in 6 hours ... he does 1/6 of it in an hour.
Juan works alone for 4.5 hours. In that time, he does 4.5/15 = 0.3
of the job. When his father joins him, there's only 0.7 of it to finish.
Working together, they do (1/15 + 1/6) = (2/30 + 5/30) = 7/30 of the job
each hour.
How many times do they have to do 7/30 of the job in order to finish
the 7/10 of it that remains ? That will be the number of hours they need.
(7/10) / (7/30) = 7/10 x 30/7 = <em>3 hours</em>.
Then they can knock off while it's still daylight, and go for a swim.
$35.99 includes 250 'free' minutes. anything over that is $0.2 per minute. So if she used 440 total minutes that means 440 minus 250 free minutes = 190 minutes over. 190 minutes times $0.2/minute = $38 extra
Total = 35.99 + 38 = 73.99
it's to 2.5 cuz u divide 5/2=2.5