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Finding the Fourth Proportional to 830.49, 1,246.28 and 420.09

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Solution

The fourth proportional to 830.49, 1,246.28 and 420.09 is: 630.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.49 : 1,246.28 = 420.09 : x
  2. Step 2: Convert to fraction form
    830.49/1,246.28 = 420.09/x
  3. Step 3: Cross multiply
    830.49x = 1,246.28 × 420.09
  4. Step 4: Simplify right side
    830.49x = 523,547.66
  5. Step 5: Solve for x
    x = 523,547.66/830.49
  6. Step 6: Final answer
    x = 630.41

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.