Home / 251-309

Finding the Third Proportional to 251 and 309

Calculator

Solution

The third proportional to 251 and 309 is: 380.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    251 : 309 = 309 : x
  2. Step 2: Convert to fraction form
    251/309 = 309/x
  3. Step 3: Cross multiply
    251x = 309 × 309
  4. Step 4: Simplify right side
    251x = 95,481
  5. Step 5: Solve for x
    x = 95,481/251
  6. Step 6: Final answer
    x = 380.40

Related Problems

Find third proportional to 125.50 and 154.50
Half scale
Find third proportional to 502 and 618
Double scale
Find third proportional to 253 and 311
Similar ratio
Find third proportional to 376.50 and 463.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.23) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.