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Finding the Fourth Proportional to 642.30, 886.20 and 380.22

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Solution

The fourth proportional to 642.30, 886.20 and 380.22 is: 524.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.30 : 886.20 = 380.22 : x
  2. Step 2: Convert to fraction form
    642.30/886.20 = 380.22/x
  3. Step 3: Cross multiply
    642.30x = 886.20 × 380.22
  4. Step 4: Simplify right side
    642.30x = 336,950.96
  5. Step 5: Solve for x
    x = 336,950.96/642.30
  6. Step 6: Final answer
    x = 524.60

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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.