Home / 761.28-1,141.20-298.72

Finding the Fourth Proportional to 761.28, 1,141.20 and 298.72

Calculator

Solution

The fourth proportional to 761.28, 1,141.20 and 298.72 is: 447.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    761.28 : 1,141.20 = 298.72 : x
  2. Step 2: Convert to fraction form
    761.28/1,141.20 = 298.72/x
  3. Step 3: Cross multiply
    761.28x = 1,141.20 × 298.72
  4. Step 4: Simplify right side
    761.28x = 340,899.26
  5. Step 5: Solve for x
    x = 340,899.26/761.28
  6. Step 6: Final answer
    x = 447.80

Related Problems

Find fourth proportional to 380.64, 570.60 and 149.36
Half scale
Find fourth proportional to 1,522.56, 2,282.40 and 597.44
Double scale
Find fourth proportional to 762.28, 1,142.70 and 299.72
Similar ratio
Find fourth proportional to 1,141.92, 1,711.80 and 448.08
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.