Finding the Fourth Proportional to 128,428.20, 192,642.30 and 86,437.80
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Solution
The fourth proportional to 128,428.20, 192,642.30 and 86,437.80 is: 129,656.70
Step by Step Solution
- Step 1: Write the proportion equation
128,428.20 : 192,642.30 = 86,437.80 : x - Step 2: Convert to fraction form
128,428.20/192,642.30 = 86,437.80/x - Step 3: Cross multiply
128,428.20x = 192,642.30 × 86,437.80 - Step 4: Simplify right side
128,428.20x = 16,651,576,598.94 - Step 5: Solve for x
x = 16,651,576,598.94/128,428.20 - Step 6: Final answer
x = 129,656.70
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1.5x scale
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.