Finding the Fourth Proportional to 1,987.30, 2,980.77 and 947.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,987.30 : 2,980.77 = 947.98 : x
2. Step 2: Convert to fraction form
   1,987.30/2,980.77 = 947.98/x
3. Step 3: Cross multiply
   1,987.30x = 2,980.77 × 947.98
4. Step 4: Simplify right side
   1,987.30x = 2,825,710.34
5. Step 5: Solve for x
   x = 2,825,710.34/1,987.30
6. Step 6: Final answer
   x = 1,421.88