Finding the Fourth Proportional to 99.81, 149.49 and 78.12
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Solution
The fourth proportional to 99.81, 149.49 and 78.12 is: 117.00
Step by Step Solution
- Step 1: Write the proportion equation
99.81 : 149.49 = 78.12 : x - Step 2: Convert to fraction form
99.81/149.49 = 78.12/x - Step 3: Cross multiply
99.81x = 149.49 × 78.12 - Step 4: Simplify right side
99.81x = 11,678.16 - Step 5: Solve for x
x = 11,678.16/99.81 - Step 6: Final answer
x = 117.00
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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.