Write the following sentence using brackets:

Multiply the difference between $8.45$ and $6.75$ by the sum of $3.2$ and $2.4$.

Write the following sentence using brackets:

Subtract the difference between $8$ and $3$ from twice the sum of $5$ and $11$.

Write the following sentence using brackets:

Divide the sum of $\frac{4}{7}$ and $\frac{5}{9}$ by $\frac{7}{8}$.

Write the following sentence using brackets:

Add the sum of $5$ and $10$, the difference of $7$ and $3$ and the product of $8$ and $25$.

Solve the following:

$2a+4\left(a+5b\right)$

Solve the following:

$30-15\left(4x-2y\right)$

Solve the following:

$4.5+2.5\left(3.5+8.5\right)$

Solve the following:

$12.8-3.2\left(4-2.8\right)$

Solve the following:

$\frac{3}{4}+\frac{11}{19}\left(\frac{6}{11}+\frac{7}{22}\right)$