Home / 258.50-398

Finding the Third Proportional to 258.50 and 398

Calculator

Solution

The third proportional to 258.50 and 398 is: 612.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.50 : 398 = 398 : x
  2. Step 2: Convert to fraction form
    258.50/398 = 398/x
  3. Step 3: Cross multiply
    258.50x = 398 × 398
  4. Step 4: Simplify right side
    258.50x = 158,404
  5. Step 5: Solve for x
    x = 158,404/258.50
  6. Step 6: Final answer
    x = 612.78

Related Problems

Find third proportional to 129.25 and 199
Half scale
Find third proportional to 517 and 796
Double scale
Find third proportional to 261 and 401
Similar ratio
Find third proportional to 387.75 and 597
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.54) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.