Home / 59.31-81.90-42.90

Finding the Fourth Proportional to 59.31, 81.90 and 42.90

Calculator

Solution

The fourth proportional to 59.31, 81.90 and 42.90 is: 59.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    59.31 : 81.90 = 42.90 : x
  2. Step 2: Convert to fraction form
    59.31/81.90 = 42.90/x
  3. Step 3: Cross multiply
    59.31x = 81.90 × 42.90
  4. Step 4: Simplify right side
    59.31x = 3,513.51
  5. Step 5: Solve for x
    x = 3,513.51/59.31
  6. Step 6: Final answer
    x = 59.24

Related Problems

Find fourth proportional to 29.66, 40.95 and 21.45
Half scale
Find fourth proportional to 118.62, 163.80 and 85.80
Double scale
Find fourth proportional to 60.31, 83.28 and 43.90
Similar ratio
Find fourth proportional to 88.97, 122.85 and 64.35
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.