Home / 645.24-890.10-424.20

Finding the Fourth Proportional to 645.24, 890.10 and 424.20

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Solution

The fourth proportional to 645.24, 890.10 and 424.20 is: 585.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.24 : 890.10 = 424.20 : x
  2. Step 2: Convert to fraction form
    645.24/890.10 = 424.20/x
  3. Step 3: Cross multiply
    645.24x = 890.10 × 424.20
  4. Step 4: Simplify right side
    645.24x = 377,580.42
  5. Step 5: Solve for x
    x = 377,580.42/645.24
  6. Step 6: Final answer
    x = 585.18

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.