Home / 512.80-707.67-279.93

Finding the Fourth Proportional to 512.80, 707.67 and 279.93

Calculator

Solution

The fourth proportional to 512.80, 707.67 and 279.93 is: 386.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.80 : 707.67 = 279.93 : x
  2. Step 2: Convert to fraction form
    512.80/707.67 = 279.93/x
  3. Step 3: Cross multiply
    512.80x = 707.67 × 279.93
  4. Step 4: Simplify right side
    512.80x = 198,098.06
  5. Step 5: Solve for x
    x = 198,098.06/512.80
  6. Step 6: Final answer
    x = 386.31

Related Problems

Find fourth proportional to 256.40, 353.84 and 139.97
Half scale
Find fourth proportional to 1,025.60, 1,415.34 and 559.86
Double scale
Find fourth proportional to 513.80, 709.05 and 280.93
Similar ratio
Find fourth proportional to 769.20, 1,061.51 and 419.90
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.