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Finding the Fourth Proportional to 684.76, 945.04 and 390.08

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Solution

The fourth proportional to 684.76, 945.04 and 390.08 is: 538.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.76 : 945.04 = 390.08 : x
  2. Step 2: Convert to fraction form
    684.76/945.04 = 390.08/x
  3. Step 3: Cross multiply
    684.76x = 945.04 × 390.08
  4. Step 4: Simplify right side
    684.76x = 368,641.20
  5. Step 5: Solve for x
    x = 368,641.20/684.76
  6. Step 6: Final answer
    x = 538.35

Related Problems

Find fourth proportional to 342.38, 472.52 and 195.04
Half scale
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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.