Home / 645.01-890.12-383.18

Finding the Fourth Proportional to 645.01, 890.12 and 383.18

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Solution

The fourth proportional to 645.01, 890.12 and 383.18 is: 528.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.01 : 890.12 = 383.18 : x
  2. Step 2: Convert to fraction form
    645.01/890.12 = 383.18/x
  3. Step 3: Cross multiply
    645.01x = 890.12 × 383.18
  4. Step 4: Simplify right side
    645.01x = 341,072.69
  5. Step 5: Solve for x
    x = 341,072.69/645.01
  6. Step 6: Final answer
    x = 528.79

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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.