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Finding the Fourth Proportional to 897.21, 1,238.10 and 498.90

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Solution

The fourth proportional to 897.21, 1,238.10 and 498.90 is: 688.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    897.21 : 1,238.10 = 498.90 : x
  2. Step 2: Convert to fraction form
    897.21/1,238.10 = 498.90/x
  3. Step 3: Cross multiply
    897.21x = 1,238.10 × 498.90
  4. Step 4: Simplify right side
    897.21x = 617,688.09
  5. Step 5: Solve for x
    x = 617,688.09/897.21
  6. Step 6: Final answer
    x = 688.45

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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.