Home / 58.80-81.57-56.91

Finding the Fourth Proportional to 58.80, 81.57 and 56.91

Calculator

Solution

The fourth proportional to 58.80, 81.57 and 56.91 is: 78.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    58.80 : 81.57 = 56.91 : x
  2. Step 2: Convert to fraction form
    58.80/81.57 = 56.91/x
  3. Step 3: Cross multiply
    58.80x = 81.57 × 56.91
  4. Step 4: Simplify right side
    58.80x = 4,642.15
  5. Step 5: Solve for x
    x = 4,642.15/58.80
  6. Step 6: Final answer
    x = 78.95

Related Problems

Find fourth proportional to 29.40, 40.79 and 28.46
Half scale
Find fourth proportional to 117.60, 163.14 and 113.82
Double scale
Find fourth proportional to 59.80, 82.96 and 57.91
Similar ratio
Find fourth proportional to 88.20, 122.36 and 85.37
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.