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Finding the Fourth Proportional to 630.21, 870.37 and 561.51

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Solution

The fourth proportional to 630.21, 870.37 and 561.51 is: 775.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.21 : 870.37 = 561.51 : x
  2. Step 2: Convert to fraction form
    630.21/870.37 = 561.51/x
  3. Step 3: Cross multiply
    630.21x = 870.37 × 561.51
  4. Step 4: Simplify right side
    630.21x = 488,721.46
  5. Step 5: Solve for x
    x = 488,721.46/630.21
  6. Step 6: Final answer
    x = 775.49

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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.