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Finding the Fourth Proportional to 515.14, 710.78 and 305.33

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Solution

The fourth proportional to 515.14, 710.78 and 305.33 is: 421.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.14 : 710.78 = 305.33 : x
  2. Step 2: Convert to fraction form
    515.14/710.78 = 305.33/x
  3. Step 3: Cross multiply
    515.14x = 710.78 × 305.33
  4. Step 4: Simplify right side
    515.14x = 217,017.38
  5. Step 5: Solve for x
    x = 217,017.38/515.14
  6. Step 6: Final answer
    x = 421.28

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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.