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Finding the Fourth Proportional to 645.10, 889.29 and 556.19

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Solution

The fourth proportional to 645.10, 889.29 and 556.19 is: 766.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.10 : 889.29 = 556.19 : x
  2. Step 2: Convert to fraction form
    645.10/889.29 = 556.19/x
  3. Step 3: Cross multiply
    645.10x = 889.29 × 556.19
  4. Step 4: Simplify right side
    645.10x = 494,614.21
  5. Step 5: Solve for x
    x = 494,614.21/645.10
  6. Step 6: Final answer
    x = 766.72

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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.