Home / 315-669

Finding the Third Proportional to 315 and 669

Calculator

Solution

The third proportional to 315 and 669 is: 1,420.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    315 : 669 = 669 : x
  2. Step 2: Convert to fraction form
    315/669 = 669/x
  3. Step 3: Cross multiply
    315x = 669 × 669
  4. Step 4: Simplify right side
    315x = 447,561
  5. Step 5: Solve for x
    x = 447,561/315
  6. Step 6: Final answer
    x = 1,420.83

Related Problems

Find third proportional to 157.50 and 334.50
Half scale
Find third proportional to 630 and 1,338
Double scale
Find third proportional to 317 and 673
Similar ratio
Find third proportional to 472.50 and 1,003.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.12) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.