If we split the fi rst circle in half again, it will be divided into four equal parts just like the second circle. Now, 2 4 of the fi rst circle is shaded, and we can add 2 4 1 4 because fourths are equally-sized pieces of the circle. 2 4 1 5 1 4 3 4 1 5 2 4 1 2 is equivalent to . Therefore, 1 2 1 4 2 4 1 4 3 4 . Let’s see how we can add 1 2 1 4 using number lines. 0 1 1 2 0 1 1 4 2 4 3 4 (or 2) 2 (or 4) 4 In order to add 1 2 1 4 using a number line, the denominators must be the same. Do you see on the number lines that 1 2 2 4 ? To add 1 2 1 4 on a number line, write 1 2 as 2 4 . Then, use the number line where the space between each tick mark is 1 4 unit to add the fractions. In order to add 1 2 1 4 3 4 1 2 1 1 4 5 2 4 1 5 3 4 (or 4) 1 4 0 1 1 4 2 4 4 (or any fractions), they must be like fractions. In other words, the fractions must have a common denominator. The same is true for subtraction. Note In order to add or subtract fractions, they must have a common denominator. Procedure Adding or Subtracting Unlike Fractions Step 1: Determine the least common denominator (LCD), and write it on your paper. Step 2: Rewrite each fraction with the LCD. Step 3: Add or subtract. Step 4: Write the answer in lowest terms. Note After finding the sum or difference, look at the result and ask yourself, “Is the answer in lowest terms?” If not, write it in lowest terms. www.mhhe.com/messersmith SECTION 4.4 Adding and Subtracting Unlike Fractions 243
messersmith_power_basic_college_1e_ch4_7_10
To see the actual publication please follow the link above