221+342−163=
To solve this problem, we begin by converting each mixed number to an improper fraction:
- 221: Convert using the formula cac+b, where a=2, b=1, and c=2. The improper fraction is 22×2+1=25.
- 342: Using the same formula, where a=3, b=2, and c=4. The improper fraction is 43×4+2=414, which simplifies to 27.
- 163: Again, using the formula, where a=1, b=3, and c=6. The improper fraction is 61×6+3=69, which simplifies to 23.
Next, we perform the addition and subtraction:
25+27−23
All fractions have the common denominator 2, so we can directly add and subtract the numerators:
(5+7−3)/2=29
Finally, convert the improper fraction 29 back to a mixed number:
9÷2=4 with a remainder of 1, so 29=421.
Therefore, the final solution to the problem is 421.