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Finding the Fourth Proportional to 621.40, 857.70 and 447.24

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Solution

The fourth proportional to 621.40, 857.70 and 447.24 is: 617.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.40 : 857.70 = 447.24 : x
  2. Step 2: Convert to fraction form
    621.40/857.70 = 447.24/x
  3. Step 3: Cross multiply
    621.40x = 857.70 × 447.24
  4. Step 4: Simplify right side
    621.40x = 383,597.75
  5. Step 5: Solve for x
    x = 383,597.75/621.40
  6. Step 6: Final answer
    x = 617.31

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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.