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Finding the Fourth Proportional to 642.56, 886.88 and 380.64

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Solution

The fourth proportional to 642.56, 886.88 and 380.64 is: 525.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.56 : 886.88 = 380.64 : x
  2. Step 2: Convert to fraction form
    642.56/886.88 = 380.64/x
  3. Step 3: Cross multiply
    642.56x = 886.88 × 380.64
  4. Step 4: Simplify right side
    642.56x = 337,582.00
  5. Step 5: Solve for x
    x = 337,582.00/642.56
  6. Step 6: Final answer
    x = 525.37

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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.