Finding the Fourth Proportional to 991.64, 1,488.18 and 479
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Solution
The fourth proportional to 991.64, 1,488.18 and 479 is: 718.85
Step by Step Solution
- Step 1: Write the proportion equation
991.64 : 1,488.18 = 479 : x - Step 2: Convert to fraction form
991.64/1,488.18 = 479/x - Step 3: Cross multiply
991.64x = 1,488.18 × 479 - Step 4: Simplify right side
991.64x = 712,838.22 - Step 5: Solve for x
x = 712,838.22/991.64 - Step 6: Final answer
x = 718.85
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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.