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Finding the Fourth Proportional to 507.80, 700.90 and 311.40

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Solution

The fourth proportional to 507.80, 700.90 and 311.40 is: 429.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    507.80 : 700.90 = 311.40 : x
  2. Step 2: Convert to fraction form
    507.80/700.90 = 311.40/x
  3. Step 3: Cross multiply
    507.80x = 700.90 × 311.40
  4. Step 4: Simplify right side
    507.80x = 218,260.26
  5. Step 5: Solve for x
    x = 218,260.26/507.80
  6. Step 6: Final answer
    x = 429.82

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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.