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Finding the Fourth Proportional to 612.90, 845.37 and 388.76

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Solution

The fourth proportional to 612.90, 845.37 and 388.76 is: 536.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.90 : 845.37 = 388.76 : x
  2. Step 2: Convert to fraction form
    612.90/845.37 = 388.76/x
  3. Step 3: Cross multiply
    612.90x = 845.37 × 388.76
  4. Step 4: Simplify right side
    612.90x = 328,641.81
  5. Step 5: Solve for x
    x = 328,641.81/612.90
  6. Step 6: Final answer
    x = 536.21

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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.