Home / 870-1,200.60-538.20

Finding the Fourth Proportional to 870, 1,200.60 and 538.20

Calculator

Solution

The fourth proportional to 870, 1,200.60 and 538.20 is: 742.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    870 : 1,200.60 = 538.20 : x
  2. Step 2: Convert to fraction form
    870/1,200.60 = 538.20/x
  3. Step 3: Cross multiply
    870x = 1,200.60 × 538.20
  4. Step 4: Simplify right side
    870x = 646,162.92
  5. Step 5: Solve for x
    x = 646,162.92/870
  6. Step 6: Final answer
    x = 742.72

Related Problems

Find fourth proportional to 435, 600.30 and 269.10
Half scale
Find fourth proportional to 1,740, 2,401.20 and 1,076.40
Double scale
Find fourth proportional to 871, 1,201.98 and 539.20
Similar ratio
Find fourth proportional to 1,305, 1,800.90 and 807.30
1.5x scale

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.