Home / 234.90-351.54-138.78

Finding the Fourth Proportional to 234.90, 351.54 and 138.78

Calculator

Solution

The fourth proportional to 234.90, 351.54 and 138.78 is: 207.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    234.90 : 351.54 = 138.78 : x
  2. Step 2: Convert to fraction form
    234.90/351.54 = 138.78/x
  3. Step 3: Cross multiply
    234.90x = 351.54 × 138.78
  4. Step 4: Simplify right side
    234.90x = 48,786.72
  5. Step 5: Solve for x
    x = 48,786.72/234.90
  6. Step 6: Final answer
    x = 207.69

Related Problems

Find fourth proportional to 117.45, 175.77 and 69.39
Half scale
Find fourth proportional to 469.80, 703.08 and 277.56
Double scale
Find fourth proportional to 235.90, 353.04 and 139.78
Similar ratio
Find fourth proportional to 352.35, 527.31 and 208.17
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.