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Finding the Fourth Proportional to 619.40, 929.10 and 615.80

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Solution

The fourth proportional to 619.40, 929.10 and 615.80 is: 923.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.40 : 929.10 = 615.80 : x
  2. Step 2: Convert to fraction form
    619.40/929.10 = 615.80/x
  3. Step 3: Cross multiply
    619.40x = 929.10 × 615.80
  4. Step 4: Simplify right side
    619.40x = 572,139.78
  5. Step 5: Solve for x
    x = 572,139.78/619.40
  6. Step 6: Final answer
    x = 923.70

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.