Home / 645.15-890.37-383.16

Finding the Fourth Proportional to 645.15, 890.37 and 383.16

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Solution

The fourth proportional to 645.15, 890.37 and 383.16 is: 528.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.15 : 890.37 = 383.16 : x
  2. Step 2: Convert to fraction form
    645.15/890.37 = 383.16/x
  3. Step 3: Cross multiply
    645.15x = 890.37 × 383.16
  4. Step 4: Simplify right side
    645.15x = 341,154.17
  5. Step 5: Solve for x
    x = 341,154.17/645.15
  6. Step 6: Final answer
    x = 528.80

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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.