Finding the Fourth Proportional to 318.40, 438.08 and 279.68
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Solution
The fourth proportional to 318.40, 438.08 and 279.68 is: 384.81
Step by Step Solution
- Step 1: Write the proportion equation
318.40 : 438.08 = 279.68 : x - Step 2: Convert to fraction form
318.40/438.08 = 279.68/x - Step 3: Cross multiply
318.40x = 438.08 × 279.68 - Step 4: Simplify right side
318.40x = 122,522.21 - Step 5: Solve for x
x = 122,522.21/318.40 - Step 6: Final answer
x = 384.81
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.