Home / 1,128.20-1,691.28-434.39

Finding the Fourth Proportional to 1,128.20, 1,691.28 and 434.39

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Solution

The fourth proportional to 1,128.20, 1,691.28 and 434.39 is: 651.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,128.20 : 1,691.28 = 434.39 : x
  2. Step 2: Convert to fraction form
    1,128.20/1,691.28 = 434.39/x
  3. Step 3: Cross multiply
    1,128.20x = 1,691.28 × 434.39
  4. Step 4: Simplify right side
    1,128.20x = 734,666.66
  5. Step 5: Solve for x
    x = 734,666.66/1,128.20
  6. Step 6: Final answer
    x = 651.19

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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.