Finding the Fourth Proportional to 1,374.76, 2,066.46 and 991.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,374.76 : 2,066.46 = 991.72 : x
2. Step 2: Convert to fraction form
   1,374.76/2,066.46 = 991.72/x
3. Step 3: Cross multiply
   1,374.76x = 2,066.46 × 991.72
4. Step 4: Simplify right side
   1,374.76x = 2,049,349.71
5. Step 5: Solve for x
   x = 2,049,349.71/1,374.76
6. Step 6: Final answer
   x = 1,490.70