Home / 344.19-516.15-138.78

Finding the Fourth Proportional to 344.19, 516.15 and 138.78

Calculator

Solution

The fourth proportional to 344.19, 516.15 and 138.78 is: 208.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    344.19 : 516.15 = 138.78 : x
  2. Step 2: Convert to fraction form
    344.19/516.15 = 138.78/x
  3. Step 3: Cross multiply
    344.19x = 516.15 × 138.78
  4. Step 4: Simplify right side
    344.19x = 71,631.30
  5. Step 5: Solve for x
    x = 71,631.30/344.19
  6. Step 6: Final answer
    x = 208.12

Related Problems

Find fourth proportional to 172.10, 258.08 and 69.39
Half scale
Find fourth proportional to 688.38, 1,032.30 and 277.56
Double scale
Find fourth proportional to 345.19, 517.65 and 139.78
Similar ratio
Find fourth proportional to 516.29, 774.23 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.