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Finding the Fourth Proportional to 714.85, 986.50 and 420.12

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Solution

The fourth proportional to 714.85, 986.50 and 420.12 is: 579.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    714.85 : 986.50 = 420.12 : x
  2. Step 2: Convert to fraction form
    714.85/986.50 = 420.12/x
  3. Step 3: Cross multiply
    714.85x = 986.50 × 420.12
  4. Step 4: Simplify right side
    714.85x = 414,448.38
  5. Step 5: Solve for x
    x = 414,448.38/714.85
  6. Step 6: Final answer
    x = 579.77

Related Problems

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Double scale
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Similar ratio
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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.