Home / 318.94-690.19

Finding the Third Proportional to 318.94 and 690.19

Calculator

Solution

The third proportional to 318.94 and 690.19 is: 1,493.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    318.94 : 690.19 = 690.19 : x
  2. Step 2: Convert to fraction form
    318.94/690.19 = 690.19/x
  3. Step 3: Cross multiply
    318.94x = 690.19 × 690.19
  4. Step 4: Simplify right side
    318.94x = 476,358.79
  5. Step 5: Solve for x
    x = 476,358.79/318.94
  6. Step 6: Final answer
    x = 1,493.58

Related Problems

Find third proportional to 159.47 and 345.09
Half scale
Find third proportional to 637.88 and 1,380.38
Double scale
Find third proportional to 321 and 695
Similar ratio
Find third proportional to 478.41 and 1,035.28
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.