Home / 55.40-83.05-38.30

Finding the Fourth Proportional to 55.40, 83.05 and 38.30

Calculator

Solution

The fourth proportional to 55.40, 83.05 and 38.30 is: 57.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.40 : 83.05 = 38.30 : x
  2. Step 2: Convert to fraction form
    55.40/83.05 = 38.30/x
  3. Step 3: Cross multiply
    55.40x = 83.05 × 38.30
  4. Step 4: Simplify right side
    55.40x = 3,180.30
  5. Step 5: Solve for x
    x = 3,180.30/55.40
  6. Step 6: Final answer
    x = 57.41

Related Problems

Find fourth proportional to 27.70, 41.52 and 19.15
Half scale
Find fourth proportional to 110.79, 166.10 and 76.59
Double scale
Find fourth proportional to 56.40, 84.55 and 39.30
Similar ratio
Find fourth proportional to 83.09, 124.57 and 57.44
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.