Home / 57-78.20-57

Finding the Fourth Proportional to 57, 78.20 and 57

Calculator

Solution

The fourth proportional to 57, 78.20 and 57 is: 78.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    57 : 78.20 = 57 : x
  2. Step 2: Convert to fraction form
    57/78.20 = 57/x
  3. Step 3: Cross multiply
    57x = 78.20 × 57
  4. Step 4: Simplify right side
    57x = 4,457.40
  5. Step 5: Solve for x
    x = 4,457.40/57
  6. Step 6: Final answer
    x = 78.20

Related Problems

Find fourth proportional to 28.50, 39.10 and 28.50
Half scale
Find fourth proportional to 114, 156.40 and 114
Double scale
Find fourth proportional to 58, 79.57 and 58
Similar ratio
Find fourth proportional to 85.50, 117.30 and 85.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.