Can I get help with this question

Given the following utility function: U = 4X + 20Y and marginal utilities MU, = 4, MU, = 20 A consumer facing the following prices P. = $10, P =5 chooses to consume: 7 units of good X and 20 units of good Y. Assume that graphically good X is on the horizontal axis and good Y is on the vertical axis. Given this consumption bundle, the marginal rate of substitution is equal to (Round your answer to two decimal places. Note that the minus sign is already included ). Given this value, the consumer should consume in order to maximize his/her utility