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Finding the Fourth Proportional to 505.70, 698.12 and 340.78

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Solution

The fourth proportional to 505.70, 698.12 and 340.78 is: 470.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.70 : 698.12 = 340.78 : x
  2. Step 2: Convert to fraction form
    505.70/698.12 = 340.78/x
  3. Step 3: Cross multiply
    505.70x = 698.12 × 340.78
  4. Step 4: Simplify right side
    505.70x = 237,904.44
  5. Step 5: Solve for x
    x = 237,904.44/505.70
  6. Step 6: Final answer
    x = 470.45

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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.