Home / 1,279.72-1,918-663.07

Finding the Fourth Proportional to 1,279.72, 1,918 and 663.07

Calculator

Solution

The fourth proportional to 1,279.72, 1,918 and 663.07 is: 993.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.72 : 1,918 = 663.07 : x
  2. Step 2: Convert to fraction form
    1,279.72/1,918 = 663.07/x
  3. Step 3: Cross multiply
    1,279.72x = 1,918 × 663.07
  4. Step 4: Simplify right side
    1,279.72x = 1,271,768.26
  5. Step 5: Solve for x
    x = 1,271,768.26/1,279.72
  6. Step 6: Final answer
    x = 993.79

Related Problems

Find fourth proportional to 639.86, 959 and 331.54
Half scale
Find fourth proportional to 2,559.44, 3,836 and 1,326.14
Double scale
Find fourth proportional to 1,280.72, 1,919.50 and 664.07
Similar ratio
Find fourth proportional to 1,919.58, 2,877 and 994.61
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.