Finding the Fourth Proportional to 91.84, 137.12 and 78.34

Step by Step Solution

1. Step 1: Write the proportion equation
   91.84 : 137.12 = 78.34 : x
2. Step 2: Convert to fraction form
   91.84/137.12 = 78.34/x
3. Step 3: Cross multiply
   91.84x = 137.12 × 78.34
4. Step 4: Simplify right side
   91.84x = 10,741.98
5. Step 5: Solve for x
   x = 10,741.98/91.84
6. Step 6: Final answer
   x = 116.96