Find the value of $-7+9.1$−7+9.1.

Find the value of $4-6.1$4−6.1.

Find $-6\times0.8$−6×0.8, giving your answer as a decimal.

Find the value of $-2+1.9+7.3$−2+1.9+7.3.

Simplify numerical expressions involving integers and rational numbers, with and without the use of technology