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Finding the Fourth Proportional to 501.95, 749.06 and 428.78

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Solution

The fourth proportional to 501.95, 749.06 and 428.78 is: 639.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.95 : 749.06 = 428.78 : x
  2. Step 2: Convert to fraction form
    501.95/749.06 = 428.78/x
  3. Step 3: Cross multiply
    501.95x = 749.06 × 428.78
  4. Step 4: Simplify right side
    501.95x = 321,176.06
  5. Step 5: Solve for x
    x = 321,176.06/501.95
  6. Step 6: Final answer
    x = 639.86

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.