#### Answer

a.) True
b.) True

#### Work Step by Step

a.) $\frac{7}{11}$ $\geq$ $\frac{8}{13}$
The Least Common Denominator of 11 and 13 = 143 (They are both prime numbers and only share multiples of each other)
$\frac{91}{143}$ $\geq$ $\frac{88}{143}$
In terms of the same denominator, 91 is bigger than 88.
True
b.)-$\frac{3}{5}$ $\gt$ -$\frac{3}{4}$
The Least Common Denominator of 5 and 4 = 20
-$\frac{12}{20}$ $\gt$ -$\frac{15}{20}$
Since both numbers are negative, the number that is closer to 0 [-$\frac{12}{20}$]are bigger than the one that is farther away [-$\frac{15}{20}$]
True