Home / 206-309-120.72

Finding the Fourth Proportional to 206, 309 and 120.72

Calculator

Solution

The fourth proportional to 206, 309 and 120.72 is: 181.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    206 : 309 = 120.72 : x
  2. Step 2: Convert to fraction form
    206/309 = 120.72/x
  3. Step 3: Cross multiply
    206x = 309 × 120.72
  4. Step 4: Simplify right side
    206x = 37,302.48
  5. Step 5: Solve for x
    x = 37,302.48/206
  6. Step 6: Final answer
    x = 181.08

Related Problems

Find fourth proportional to 103, 154.50 and 60.36
Half scale
Find fourth proportional to 412, 618 and 241.44
Double scale
Find fourth proportional to 207, 310.50 and 121.72
Similar ratio
Find fourth proportional to 309, 463.50 and 181.08
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.