Finding the Fourth Proportional to 140, 210 and 79.08
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Solution
The fourth proportional to 140, 210 and 79.08 is: 118.62
Step by Step Solution
- Step 1: Write the proportion equation
140 : 210 = 79.08 : x - Step 2: Convert to fraction form
140/210 = 79.08/x - Step 3: Cross multiply
140x = 210 × 79.08 - Step 4: Simplify right side
140x = 16,606.80 - Step 5: Solve for x
x = 16,606.80/140 - Step 6: Final answer
x = 118.62
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.