12=-7n how do you do this and what s that answer its called one step eqations

Diana is painting statues she has 7/8 of a liter of paint each statue requires 1/20 of a liter of paint how many statues can she paint?

Adifferent website gives the cost for the first train as £56.88 and the second train as £20.11 with a £9.50 charge for cycle storage for the whole trip. how much would the journey cost you?

Someone answer asap for ! michele pushes a box d meters across a floor. she uses a force f, in newtons, to push the box. she pushes the box for t seconds. the formula p = fd/t calculates the power, p, in watts, that it takes for michele to complete the task. solve the formula for d.