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Finding the Fourth Proportional to 1,298.07, 1,946.69 and 420.39

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Solution

The fourth proportional to 1,298.07, 1,946.69 and 420.39 is: 630.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,298.07 : 1,946.69 = 420.39 : x
  2. Step 2: Convert to fraction form
    1,298.07/1,946.69 = 420.39/x
  3. Step 3: Cross multiply
    1,298.07x = 1,946.69 × 420.39
  4. Step 4: Simplify right side
    1,298.07x = 818,369.01
  5. Step 5: Solve for x
    x = 818,369.01/1,298.07
  6. Step 6: Final answer
    x = 630.45

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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.