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Finding the Fourth Proportional to 56.50, 78 and 39.28

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Solution

The fourth proportional to 56.50, 78 and 39.28 is: 54.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    56.50 : 78 = 39.28 : x
  2. Step 2: Convert to fraction form
    56.50/78 = 39.28/x
  3. Step 3: Cross multiply
    56.50x = 78 × 39.28
  4. Step 4: Simplify right side
    56.50x = 3,063.84
  5. Step 5: Solve for x
    x = 3,063.84/56.50
  6. Step 6: Final answer
    x = 54.23

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.