Home / 222.80-307.42-129.55

Finding the Fourth Proportional to 222.80, 307.42 and 129.55

Calculator

Solution

The fourth proportional to 222.80, 307.42 and 129.55 is: 178.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    222.80 : 307.42 = 129.55 : x
  2. Step 2: Convert to fraction form
    222.80/307.42 = 129.55/x
  3. Step 3: Cross multiply
    222.80x = 307.42 × 129.55
  4. Step 4: Simplify right side
    222.80x = 39,826.26
  5. Step 5: Solve for x
    x = 39,826.26/222.80
  6. Step 6: Final answer
    x = 178.75

Related Problems

Find fourth proportional to 111.40, 153.71 and 64.78
Half scale
Find fourth proportional to 445.60, 614.84 and 259.10
Double scale
Find fourth proportional to 223.80, 308.80 and 130.55
Similar ratio
Find fourth proportional to 334.20, 461.13 and 194.33
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.