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Finding the Fourth Proportional to 640.39, 882.85 and 430.20

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Solution

The fourth proportional to 640.39, 882.85 and 430.20 is: 593.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.39 : 882.85 = 430.20 : x
  2. Step 2: Convert to fraction form
    640.39/882.85 = 430.20/x
  3. Step 3: Cross multiply
    640.39x = 882.85 × 430.20
  4. Step 4: Simplify right side
    640.39x = 379,802.07
  5. Step 5: Solve for x
    x = 379,802.07/640.39
  6. Step 6: Final answer
    x = 593.08

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1.5x scale

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.