Finding the Fourth Proportional to 12,991, 17,927.58 and 7,402

Step by Step Solution

1. Step 1: Write the proportion equation
   12,991 : 17,927.58 = 7,402 : x
2. Step 2: Convert to fraction form
   12,991/17,927.58 = 7,402/x
3. Step 3: Cross multiply
   12,991x = 17,927.58 × 7,402
4. Step 4: Simplify right side
   12,991x = 132,699,947.16
5. Step 5: Solve for x
   x = 132,699,947.16/12,991
6. Step 6: Final answer
   x = 10,214.76