Finding the Fourth Proportional to 306, 459 and 78
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Solution
The fourth proportional to 306, 459 and 78 is: 117
Step by Step Solution
- Step 1: Write the proportion equation
306 : 459 = 78 : x - Step 2: Convert to fraction form
306/459 = 78/x - Step 3: Cross multiply
306x = 459 × 78 - Step 4: Simplify right side
306x = 35,802 - Step 5: Solve for x
x = 35,802/306 - Step 6: Final answer
x = 117
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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.