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Finding the Fourth Proportional to 612.60, 918.90 and 491.10

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Solution

The fourth proportional to 612.60, 918.90 and 491.10 is: 736.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.60 : 918.90 = 491.10 : x
  2. Step 2: Convert to fraction form
    612.60/918.90 = 491.10/x
  3. Step 3: Cross multiply
    612.60x = 918.90 × 491.10
  4. Step 4: Simplify right side
    612.60x = 451,271.79
  5. Step 5: Solve for x
    x = 451,271.79/612.60
  6. Step 6: Final answer
    x = 736.65

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Similar ratio
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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.