# Breuken optellen (reeks 2)

#### Tel de breuken op

1. $$\frac{3}{17}+\frac{2}{5}$$
2. $$\frac{-6}{7}+\frac{20}{7}$$
3. $$\frac{13}{17}+\frac{16}{11}$$
4. $$\frac{-14}{9}+\frac{17}{16}$$
5. $$\frac{-15}{13}+\frac{7}{10}$$
6. $$\frac{-17}{2}+\frac{6}{7}$$
7. $$\frac{-15}{2}+\frac{3}{4}$$
8. $$\frac{19}{5}+\frac{13}{9}$$
9. $$\frac{6}{19}+\frac{7}{9}$$
10. $$\frac{19}{7}+\frac{20}{9}$$
11. $$\frac{-19}{9}+\frac{2}{5}$$
12. $$\frac{9}{14}+\frac{3}{2}$$

#### Tel de breuken op

##### Verbetersleutel

1. $$\frac{3}{17}+\frac{2}{5}\\=\frac{15}{85}+\frac{34}{85}\\=\frac{15+34}{85}\\=\frac{49}{85}$$
2. $$\frac{-6}{7}+\frac{20}{7}\\=\frac{-6+20}{7}\\=\frac{14}{7}\\=\frac{2}{1}$$
3. $$\frac{13}{17}+\frac{16}{11}\\=\frac{143}{187}+\frac{272}{187}\\=\frac{143+272}{187}\\=\frac{415}{187}$$
4. $$\frac{-14}{9}+\frac{17}{16}\\=\frac{-224}{144}+\frac{153}{144}\\=\frac{-224+153}{144}\\=\frac{-71}{144}\\=\frac{71}{-144}$$
5. $$\frac{-15}{13}+\frac{7}{10}\\=\frac{-150}{130}+\frac{91}{130}\\=\frac{-150+91}{130}\\=\frac{-59}{130}$$
6. $$\frac{-17}{2}+\frac{6}{7}\\=\frac{-119}{14}+\frac{12}{14}\\=\frac{-119+12}{14}\\=\frac{-107}{14}$$
7. $$\frac{-15}{2}+\frac{3}{4}\\=\frac{-30}{4}+\frac{3}{4}\\=\frac{-30+3}{4}\\=\frac{-27}{4}$$
8. $$\frac{19}{5}+\frac{13}{9}\\=\frac{171}{45}+\frac{65}{45}\\=\frac{171+65}{45}\\=\frac{236}{45}$$
9. $$\frac{6}{19}+\frac{7}{9}\\=\frac{54}{171}+\frac{133}{171}\\=\frac{54+133}{171}\\=\frac{187}{171}$$
10. $$\frac{19}{7}+\frac{20}{9}\\=\frac{171}{63}+\frac{140}{63}\\=\frac{171+140}{63}\\=\frac{311}{63}$$
11. $$\frac{-19}{9}+\frac{2}{5}\\=\frac{-95}{45}+\frac{18}{45}\\=\frac{-95+18}{45}\\=\frac{-77}{45}$$
12. $$\frac{9}{14}+\frac{3}{2}\\=\frac{9+3}{14}\\=\frac{12}{14}\\=\frac{6}{7}$$
Oefeningengenerator vanhoeckes.be/wiskunde 2021-12-02 01:46:59