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Finding the Fourth Proportional to 784.86, 1,078.64 and 644.74

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Solution

The fourth proportional to 784.86, 1,078.64 and 644.74 is: 886.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    784.86 : 1,078.64 = 644.74 : x
  2. Step 2: Convert to fraction form
    784.86/1,078.64 = 644.74/x
  3. Step 3: Cross multiply
    784.86x = 1,078.64 × 644.74
  4. Step 4: Simplify right side
    784.86x = 695,442.35
  5. Step 5: Solve for x
    x = 695,442.35/784.86
  6. Step 6: Final answer
    x = 886.07

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 (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.