Finding the Fourth Proportional to 90,986.58, 136,494.72 and 28,642.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90,986.58 : 136,494.72 = 28,642.50 : x
2. Step 2: Convert to fraction form
   90,986.58/136,494.72 = 28,642.50/x
3. Step 3: Cross multiply
   90,986.58x = 136,494.72 × 28,642.50
4. Step 4: Simplify right side
   90,986.58x = 3,909,550,017.60
5. Step 5: Solve for x
   x = 3,909,550,017.60/90,986.58
6. Step 6: Final answer
   x = 42,968.42