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Finding the Fourth Proportional to 500.30, 690.42 and 279.26

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Solution

The fourth proportional to 500.30, 690.42 and 279.26 is: 385.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    500.30 : 690.42 = 279.26 : x
  2. Step 2: Convert to fraction form
    500.30/690.42 = 279.26/x
  3. Step 3: Cross multiply
    500.30x = 690.42 × 279.26
  4. Step 4: Simplify right side
    500.30x = 192,806.69
  5. Step 5: Solve for x
    x = 192,806.69/500.30
  6. Step 6: Final answer
    x = 385.38

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Double scale
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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.