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Finding the Fourth Proportional to 840.69, 1,159.20 and 663.66

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Solution

The fourth proportional to 840.69, 1,159.20 and 663.66 is: 915.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.69 : 1,159.20 = 663.66 : x
  2. Step 2: Convert to fraction form
    840.69/1,159.20 = 663.66/x
  3. Step 3: Cross multiply
    840.69x = 1,159.20 × 663.66
  4. Step 4: Simplify right side
    840.69x = 769,314.67
  5. Step 5: Solve for x
    x = 769,314.67/840.69
  6. Step 6: Final answer
    x = 915.10

Related Problems

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Half scale
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Double scale
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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.