Finding the Fourth Proportional to 1,112.61, 1,667.80 and 526.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,112.61 : 1,667.80 = 526.56 : x
2. Step 2: Convert to fraction form
   1,112.61/1,667.80 = 526.56/x
3. Step 3: Cross multiply
   1,112.61x = 1,667.80 × 526.56
4. Step 4: Simplify right side
   1,112.61x = 878,196.77
5. Step 5: Solve for x
   x = 878,196.77/1,112.61
6. Step 6: Final answer
   x = 789.31