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Finding the Fourth Proportional to 628.32, 867.12 and 621.60

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Solution

The fourth proportional to 628.32, 867.12 and 621.60 is: 857.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.32 : 867.12 = 621.60 : x
  2. Step 2: Convert to fraction form
    628.32/867.12 = 621.60/x
  3. Step 3: Cross multiply
    628.32x = 867.12 × 621.60
  4. Step 4: Simplify right side
    628.32x = 539,001.79
  5. Step 5: Solve for x
    x = 539,001.79/628.32
  6. Step 6: Final answer
    x = 857.85

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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.