Home / 518-690

Finding the Third Proportional to 518 and 690

Calculator

Solution

The third proportional to 518 and 690 is: 919.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    518 : 690 = 690 : x
  2. Step 2: Convert to fraction form
    518/690 = 690/x
  3. Step 3: Cross multiply
    518x = 690 × 690
  4. Step 4: Simplify right side
    518x = 476,100
  5. Step 5: Solve for x
    x = 476,100/518
  6. Step 6: Final answer
    x = 919.11

Related Problems

Why These Related Problems?

These problems maintain the same ratio (1.33) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.