Question 1054203
How many gallons of a 10% salt solution should be added to 20 gallons of a 60% salt solution to obtain a 50% salt solution?

The perimeter of a rectangle is 40 cm more than four times its width and the length is 2 cm more than twice its width. What is the area of the rectangle.

Working alone, Christian can finish a job in 6 hours.   Requesting  Aron to work with him, the two can finish the same job in 4 and 1/2 hours.  How long would it take Aron to finish the same job alone? 

Urgent pls help
<pre>I'll give you the CORRECT answer to no. 2
{{{highlight_green(matrix(1,3, "Area:", 684, cm^2))}}}