Home / 758.92-1,139.72-638.76

Finding the Fourth Proportional to 758.92, 1,139.72 and 638.76

Calculator

Solution

The fourth proportional to 758.92, 1,139.72 and 638.76 is: 959.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    758.92 : 1,139.72 = 638.76 : x
  2. Step 2: Convert to fraction form
    758.92/1,139.72 = 638.76/x
  3. Step 3: Cross multiply
    758.92x = 1,139.72 × 638.76
  4. Step 4: Simplify right side
    758.92x = 728,007.55
  5. Step 5: Solve for x
    x = 728,007.55/758.92
  6. Step 6: Final answer
    x = 959.27

Related Problems

Find fourth proportional to 379.46, 569.86 and 319.38
Half scale
Find fourth proportional to 1,517.84, 2,279.44 and 1,277.52
Double scale
Find fourth proportional to 759.92, 1,141.22 and 639.76
Similar ratio
Find fourth proportional to 1,138.38, 1,709.58 and 958.14
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.