Finding the Fourth Proportional to 78.69, 117.99 and 30.54
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Solution
The fourth proportional to 78.69, 117.99 and 30.54 is: 45.79
Step by Step Solution
- Step 1: Write the proportion equation
78.69 : 117.99 = 30.54 : x - Step 2: Convert to fraction form
78.69/117.99 = 30.54/x - Step 3: Cross multiply
78.69x = 117.99 × 30.54 - Step 4: Simplify right side
78.69x = 3,603.41 - Step 5: Solve for x
x = 3,603.41/78.69 - Step 6: Final answer
x = 45.79
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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.