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Finding the Fourth Proportional to 684.95, 945.23 and 390.32

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Solution

The fourth proportional to 684.95, 945.23 and 390.32 is: 538.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.95 : 945.23 = 390.32 : x
  2. Step 2: Convert to fraction form
    684.95/945.23 = 390.32/x
  3. Step 3: Cross multiply
    684.95x = 945.23 × 390.32
  4. Step 4: Simplify right side
    684.95x = 368,935.50
  5. Step 5: Solve for x
    x = 368,935.50/684.95
  6. Step 6: Final answer
    x = 538.64

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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.