[tex] \sf \frac{2}{5} < \frac{7}{12} \: is \: true[/tex]
We will cross multiply the fraction and check them!
To compare the fraction we need common denominators.
Let's solve~
#1
[tex] \sf \frac{2}{5} < \frac{7}{12} \\ \sf 2 \times 12 < 5 \times 7 \\ \sf 24 < 35 \\ \tt true[/tex]
[tex]\rule{300pt}{3pt}[/tex]
#2
[tex] \sf \frac{2}{3} < \frac{1}{8} \\ \sf 8 \times 2 < 3 \times 1 \\ \sf \: 16 < 3 \\ \tt \: false[/tex]
[tex]\rule{300pt}{3pt}[/tex]
#3
[tex] \sf \frac{1}{4} > \frac{7}{10} \\ \sf 10 \times 1 > 7 \times 4 \\ \sf 10 > 8 \\ \tt \: false[/tex]
[tex]\rule{300pt}{3pt}[/tex]
#4
[tex] \sf \frac{3}{10} > \frac{5}{8} \\ \sf 8 \times 3 > 10 \times 5 \\ \sf 24 > 50 \\ \tt \: false[/tex]
