Home / 1,210.28-1,815.68-430.32

Finding the Fourth Proportional to 1,210.28, 1,815.68 and 430.32

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Solution

The fourth proportional to 1,210.28, 1,815.68 and 430.32 is: 645.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.28 : 1,815.68 = 430.32 : x
  2. Step 2: Convert to fraction form
    1,210.28/1,815.68 = 430.32/x
  3. Step 3: Cross multiply
    1,210.28x = 1,815.68 × 430.32
  4. Step 4: Simplify right side
    1,210.28x = 781,321.27
  5. Step 5: Solve for x
    x = 781,321.27/1,210.28
  6. Step 6: Final answer
    x = 645.57

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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.