Home / 313.08-469.70-139.79

Finding the Fourth Proportional to 313.08, 469.70 and 139.79

Calculator

Solution

The fourth proportional to 313.08, 469.70 and 139.79 is: 209.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    313.08 : 469.70 = 139.79 : x
  2. Step 2: Convert to fraction form
    313.08/469.70 = 139.79/x
  3. Step 3: Cross multiply
    313.08x = 469.70 × 139.79
  4. Step 4: Simplify right side
    313.08x = 65,656.32
  5. Step 5: Solve for x
    x = 65,656.32/313.08
  6. Step 6: Final answer
    x = 209.71

Related Problems

Find fourth proportional to 156.54, 234.85 and 69.89
Half scale
Find fourth proportional to 626.16, 939.39 and 279.57
Double scale
Find fourth proportional to 314.08, 471.20 and 140.79
Similar ratio
Find fourth proportional to 469.62, 704.54 and 209.68
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.