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Finding the Fourth Proportional to 630.99, 870.21 and 456.30

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Solution

The fourth proportional to 630.99, 870.21 and 456.30 is: 629.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.99 : 870.21 = 456.30 : x
  2. Step 2: Convert to fraction form
    630.99/870.21 = 456.30/x
  3. Step 3: Cross multiply
    630.99x = 870.21 × 456.30
  4. Step 4: Simplify right side
    630.99x = 397,076.82
  5. Step 5: Solve for x
    x = 397,076.82/630.99
  6. Step 6: Final answer
    x = 629.29

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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.