Mahesh peaches 300 eggs at the rate of 18 should is per duzen he should her 150 eggs at a gain of 20% at what percentage should he sell remaining in order to a gain 30 % on his outlay.

This makes no sense. You have too many totally misspelled words.

To solve the problem, let's break it down step by step:

1. Mahesh purchased 300 eggs at the rate of 18 shillings per dozen. This means he bought 300/12 = 25 dozens.
2. The cost of 150 eggs is given as 20% profit. Let's calculate the cost price of those eggs:

Cost price of 150 eggs = (20/100) * Cost price
= (20/100) * (18 * 25)
= 20 * 18 * 25 / 100

3. Now, Mahesh wants to sell the remaining eggs at a gain of 30% on his outlay. Let's calculate the selling price of the remaining eggs.

Selling price of remaining eggs = Cost price of remaining eggs + 30% profit
= Cost price of remaining eggs + (30/100) * Cost price of remaining eggs
= Cost price of remaining eggs * (1 + 30/100)
= Cost price of remaining eggs * 1.3

4. To find the percentage at which he should sell the remaining eggs, we need to divide the selling price by the cost price and multiply by 100.

Percentage = (Selling price / Cost price) * 100

Now, let's substitute the values and calculate:

Cost price of 150 eggs = 20 * 18 * 25 / 100

Selling price of remaining eggs = (Cost price of 150 eggs) * 1.3

Percentage = (Selling price of remaining eggs / Cost price of remaining eggs) * 100

After substituting the values, you can compute the final answer.