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Finding the Fourth Proportional to 500.61, 690.81 and 279.57

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Solution

The fourth proportional to 500.61, 690.81 and 279.57 is: 385.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.61 : 690.81 = 279.57 : x
  2. Step 2: Convert to fraction form
    500.61/690.81 = 279.57/x
  3. Step 3: Cross multiply
    500.61x = 690.81 × 279.57
  4. Step 4: Simplify right side
    500.61x = 193,131.13
  5. Step 5: Solve for x
    x = 193,131.13/500.61
  6. Step 6: Final answer
    x = 385.79

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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.