Finding the Fourth Proportional to 819.70, 1,131.42 and 571
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Solution
The fourth proportional to 819.70, 1,131.42 and 571 is: 788.14
Step by Step Solution
- Step 1: Write the proportion equation
819.70 : 1,131.42 = 571 : x - Step 2: Convert to fraction form
819.70/1,131.42 = 571/x - Step 3: Cross multiply
819.70x = 1,131.42 × 571 - Step 4: Simplify right side
819.70x = 646,040.82 - Step 5: Solve for x
x = 646,040.82/819.70 - Step 6: Final answer
x = 788.14
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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.