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Finding the Fourth Proportional to 509.40, 702.76 and 378.72

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Solution

The fourth proportional to 509.40, 702.76 and 378.72 is: 522.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.40 : 702.76 = 378.72 : x
  2. Step 2: Convert to fraction form
    509.40/702.76 = 378.72/x
  3. Step 3: Cross multiply
    509.40x = 702.76 × 378.72
  4. Step 4: Simplify right side
    509.40x = 266,149.27
  5. Step 5: Solve for x
    x = 266,149.27/509.40
  6. Step 6: Final answer
    x = 522.48

Related Problems

Find fourth proportional to 254.70, 351.38 and 189.36
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Double scale
Find fourth proportional to 510.40, 704.14 and 379.72
Similar ratio
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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.