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Finding the Fourth Proportional to 565.06, 780.07 and 390.10

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Solution

The fourth proportional to 565.06, 780.07 and 390.10 is: 538.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    565.06 : 780.07 = 390.10 : x
  2. Step 2: Convert to fraction form
    565.06/780.07 = 390.10/x
  3. Step 3: Cross multiply
    565.06x = 780.07 × 390.10
  4. Step 4: Simplify right side
    565.06x = 304,305.31
  5. Step 5: Solve for x
    x = 304,305.31/565.06
  6. Step 6: Final answer
    x = 538.54

Related Problems

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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.