The first tank contains
486 gal - (4 gal/week) <em>t</em>
gal of water after <em>t</em> weeks.
Similarly, the second tank contains
648 gal - (7 gal/week) <em>t</em>
gal of water.
The tanks hold the same amount of water when these two amounts are equal:
486 gal - (4 gal/week) <em>t</em> = 648 gal - (7 gal/week) <em>t</em>
(7 gal/week) <em>t</em> - (4 gal/week) <em>t</em> = 648 gal - 486 gal
(3 gal/week) <em>t</em> = 162 gal
<em>t</em> = (162 gal) / (3 gal/week)
<em>t</em> = 54 weeks
Isolate the variable Y by multiplying 1.5 on both sides.
Hope this helps.
頑張って!
$81.00
30% of 270 = 0.3 × 270 = 81
6 minutes/60minutes = 0.1 hrs
45miles/0.1hour = 450 miles per hour or mph
