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Finding the Fourth Proportional to 621.40, 857.34 and 372.88

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Solution

The fourth proportional to 621.40, 857.34 and 372.88 is: 514.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.40 : 857.34 = 372.88 : x
  2. Step 2: Convert to fraction form
    621.40/857.34 = 372.88/x
  3. Step 3: Cross multiply
    621.40x = 857.34 × 372.88
  4. Step 4: Simplify right side
    621.40x = 319,684.94
  5. Step 5: Solve for x
    x = 319,684.94/621.40
  6. Step 6: Final answer
    x = 514.46

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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.