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Finding the Fourth Proportional to 690.72, 953.37 and 428.58

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Solution

The fourth proportional to 690.72, 953.37 and 428.58 is: 591.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.72 : 953.37 = 428.58 : x
  2. Step 2: Convert to fraction form
    690.72/953.37 = 428.58/x
  3. Step 3: Cross multiply
    690.72x = 953.37 × 428.58
  4. Step 4: Simplify right side
    690.72x = 408,595.31
  5. Step 5: Solve for x
    x = 408,595.31/690.72
  6. Step 6: Final answer
    x = 591.55

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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.