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Finding the Fourth Proportional to 565.80, 779.86 and 390.76

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Solution

The fourth proportional to 565.80, 779.86 and 390.76 is: 538.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    565.80 : 779.86 = 390.76 : x
  2. Step 2: Convert to fraction form
    565.80/779.86 = 390.76/x
  3. Step 3: Cross multiply
    565.80x = 779.86 × 390.76
  4. Step 4: Simplify right side
    565.80x = 304,738.09
  5. Step 5: Solve for x
    x = 304,738.09/565.80
  6. Step 6: Final answer
    x = 538.60

Related Problems

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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.