Home / 738.78-1,019.49-407.20

Finding the Fourth Proportional to 738.78, 1,019.49 and 407.20

Calculator

Solution

The fourth proportional to 738.78, 1,019.49 and 407.20 is: 561.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    738.78 : 1,019.49 = 407.20 : x
  2. Step 2: Convert to fraction form
    738.78/1,019.49 = 407.20/x
  3. Step 3: Cross multiply
    738.78x = 1,019.49 × 407.20
  4. Step 4: Simplify right side
    738.78x = 415,136.33
  5. Step 5: Solve for x
    x = 415,136.33/738.78
  6. Step 6: Final answer
    x = 561.92

Related Problems

Find fourth proportional to 369.39, 509.75 and 203.60
Half scale
Find fourth proportional to 1,477.56, 2,038.98 and 814.40
Double scale
Find fourth proportional to 739.78, 1,020.87 and 408.20
Similar ratio
Find fourth proportional to 1,108.17, 1,529.24 and 610.80
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.