Finding the Fourth Proportional to 99.76, 137.67 and 56.10

Step by Step Solution

1. Step 1: Write the proportion equation
   99.76 : 137.67 = 56.10 : x
2. Step 2: Convert to fraction form
   99.76/137.67 = 56.10/x
3. Step 3: Cross multiply
   99.76x = 137.67 × 56.10
4. Step 4: Simplify right side
   99.76x = 7,723.29
5. Step 5: Solve for x
   x = 7,723.29/99.76
6. Step 6: Final answer
   x = 77.42