Home / 408.18-611.67-215.22

Finding the Fourth Proportional to 408.18, 611.67 and 215.22

Calculator

Solution

The fourth proportional to 408.18, 611.67 and 215.22 is: 322.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.18 : 611.67 = 215.22 : x
  2. Step 2: Convert to fraction form
    408.18/611.67 = 215.22/x
  3. Step 3: Cross multiply
    408.18x = 611.67 × 215.22
  4. Step 4: Simplify right side
    408.18x = 131,643.62
  5. Step 5: Solve for x
    x = 131,643.62/408.18
  6. Step 6: Final answer
    x = 322.51

Related Problems

Find fourth proportional to 204.09, 305.84 and 107.61
Half scale
Find fourth proportional to 816.36, 1,223.34 and 430.44
Double scale
Find fourth proportional to 409.18, 613.17 and 216.22
Similar ratio
Find fourth proportional to 612.27, 917.51 and 322.83
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.