Finding the Fourth Proportional to 91,317.86, 136,987.72 and 38,720.50

Step by Step Solution

1. Step 1: Write the proportion equation
   91,317.86 : 136,987.72 = 38,720.50 : x
2. Step 2: Convert to fraction form
   91,317.86/136,987.72 = 38,720.50/x
3. Step 3: Cross multiply
   91,317.86x = 136,987.72 × 38,720.50
4. Step 4: Simplify right side
   91,317.86x = 5,304,233,012.26
5. Step 5: Solve for x
   x = 5,304,233,012.26/91,317.86
6. Step 6: Final answer
   x = 58,085.38