Decreasing the volume of a gas increases the pressure of the gas. ...More colinse mean more force, so the pressure will increase. When the volume decreases, the pressure increases. This shows that the pressure of a gas is inversely proportional to its volume.
Change in temperature
The temperature of the gas is proportional to the average kinetic energy of its molecules. Faster moving particles will collide with the container walls more frequently and with greater force. This causes the force on the walls of the container to increase and so the pressure increases.
*proportional* - in math it is said as when 2 varying quantities come together
