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Finding the Fourth Proportional to 977.09, 1,347.37 and 645.09

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Solution

The fourth proportional to 977.09, 1,347.37 and 645.09 is: 889.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    977.09 : 1,347.37 = 645.09 : x
  2. Step 2: Convert to fraction form
    977.09/1,347.37 = 645.09/x
  3. Step 3: Cross multiply
    977.09x = 1,347.37 × 645.09
  4. Step 4: Simplify right side
    977.09x = 869,174.91
  5. Step 5: Solve for x
    x = 869,174.91/977.09
  6. Step 6: Final answer
    x = 889.55

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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.