Finding the Fourth Proportional to 79.80, 119.07 and 76.20
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Solution
The fourth proportional to 79.80, 119.07 and 76.20 is: 113.70
Step by Step Solution
- Step 1: Write the proportion equation
79.80 : 119.07 = 76.20 : x - Step 2: Convert to fraction form
79.80/119.07 = 76.20/x - Step 3: Cross multiply
79.80x = 119.07 × 76.20 - Step 4: Simplify right side
79.80x = 9,073.13 - Step 5: Solve for x
x = 9,073.13/79.80 - Step 6: Final answer
x = 113.70
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.