Finding the Fourth Proportional to 8.72, 13.08 and 6
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Solution
The fourth proportional to 8.72, 13.08 and 6 is: 9
Step by Step Solution
- Step 1: Write the proportion equation
8.72 : 13.08 = 6 : x - Step 2: Convert to fraction form
8.72/13.08 = 6/x - Step 3: Cross multiply
8.72x = 13.08 × 6 - Step 4: Simplify right side
8.72x = 78.48 - Step 5: Solve for x
x = 78.48/8.72 - Step 6: Final answer
x = 9
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Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.