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Finding the Fourth Proportional to 691.16, 953.78 and 380.66

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Solution

The fourth proportional to 691.16, 953.78 and 380.66 is: 525.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.16 : 953.78 = 380.66 : x
  2. Step 2: Convert to fraction form
    691.16/953.78 = 380.66/x
  3. Step 3: Cross multiply
    691.16x = 953.78 × 380.66
  4. Step 4: Simplify right side
    691.16x = 363,065.89
  5. Step 5: Solve for x
    x = 363,065.89/691.16
  6. Step 6: Final answer
    x = 525.30

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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.