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Finding the Fourth Proportional to 678.95, 936.90 and 458.20

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Solution

The fourth proportional to 678.95, 936.90 and 458.20 is: 632.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.95 : 936.90 = 458.20 : x
  2. Step 2: Convert to fraction form
    678.95/936.90 = 458.20/x
  3. Step 3: Cross multiply
    678.95x = 936.90 × 458.20
  4. Step 4: Simplify right side
    678.95x = 429,287.58
  5. Step 5: Solve for x
    x = 429,287.58/678.95
  6. Step 6: Final answer
    x = 632.28

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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.