Home / 1,210.45-1,815.64-430.65

Finding the Fourth Proportional to 1,210.45, 1,815.64 and 430.65

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Solution

The fourth proportional to 1,210.45, 1,815.64 and 430.65 is: 645.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.45 : 1,815.64 = 430.65 : x
  2. Step 2: Convert to fraction form
    1,210.45/1,815.64 = 430.65/x
  3. Step 3: Cross multiply
    1,210.45x = 1,815.64 × 430.65
  4. Step 4: Simplify right side
    1,210.45x = 781,906.05
  5. Step 5: Solve for x
    x = 781,906.05/1,210.45
  6. Step 6: Final answer
    x = 645.96

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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.