Finding the Fourth Proportional to 99.90, 149.78 and 80.70
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Solution
The fourth proportional to 99.90, 149.78 and 80.70 is: 120.99
Step by Step Solution
- Step 1: Write the proportion equation
99.90 : 149.78 = 80.70 : x - Step 2: Convert to fraction form
99.90/149.78 = 80.70/x - Step 3: Cross multiply
99.90x = 149.78 × 80.70 - Step 4: Simplify right side
99.90x = 12,087.25 - Step 5: Solve for x
x = 12,087.25/99.90 - Step 6: Final answer
x = 120.99
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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.