Finding the Fourth Proportional to 76.80, 115.02 and 58.68
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Solution
The fourth proportional to 76.80, 115.02 and 58.68 is: 87.88
Step by Step Solution
- Step 1: Write the proportion equation
76.80 : 115.02 = 58.68 : x - Step 2: Convert to fraction form
76.80/115.02 = 58.68/x - Step 3: Cross multiply
76.80x = 115.02 × 58.68 - Step 4: Simplify right side
76.80x = 6,749.37 - Step 5: Solve for x
x = 6,749.37/76.80 - Step 6: Final answer
x = 87.88
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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.