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Finding the Fourth Proportional to 630.70, 869.04 and 420.64

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Solution

The fourth proportional to 630.70, 869.04 and 420.64 is: 579.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.70 : 869.04 = 420.64 : x
  2. Step 2: Convert to fraction form
    630.70/869.04 = 420.64/x
  3. Step 3: Cross multiply
    630.70x = 869.04 × 420.64
  4. Step 4: Simplify right side
    630.70x = 365,552.99
  5. Step 5: Solve for x
    x = 365,552.99/630.70
  6. Step 6: Final answer
    x = 579.60

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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.