Finding the Third Proportional to 31,490 and 42,579

Step by Step Solution

1. Step 1: Write the proportion equation
   31,490 : 42,579 = 42,579 : x
2. Step 2: Convert to fraction form
   31,490/42,579 = 42,579/x
3. Step 3: Cross multiply
   31,490x = 42,579 × 42,579
4. Step 4: Simplify right side
   31,490x = 1,812,971,241
5. Step 5: Solve for x
   x = 1,812,971,241/31,490
6. Step 6: Final answer
   x = 57,572.92