Onika gives money to a charity directly from her wages, before tax. One sixth of her monthly earnings goes to the charity, then one fifth of what's left gets deducted as tax. How much money goes to charity and on tax, and how much is left, if she earns £2400?

Onika gives 1/6 of her earnings to the charity before tax, which is (1/6) x £2400 = £<<1/6*2400=400>>400.

The amount left after giving £400 to charity is £2400 - £400 = £<<2400-400=2000>>2000.
Then, 1/5 of what's left is deducted as tax, which is (1/5) x £2000 = £<<1/5*2000=400>>400.
The total amount deducted for tax and charity is therefore £400 + £400 = £<<400+400=800>>800.
The amount left after the deductions is £2400 - £800 = £<<2400-800=1600>>1600. Answer: \boxed{£400} to charity, \boxed{£400} on tax, and \boxed{£1600} left.

To find out how much money goes to charity first, we need to calculate one-sixth of her monthly earnings.

One-sixth of £2400 = £2400 ÷ 6 = £<<2400/6=400>>400

So, £400 goes to charity.

Now, let's calculate how much money is left after the charity contribution.

Her remaining earnings will be 5/6 of £2400, which is (5/6) * £2400.

(5/6) * £2400 = £<<(5/6)*2400=2000>>2000

So, £2000 is left after the charity contribution.

Now, let's calculate the amount of tax deducted, which is one-fifth of the remaining earnings.

One-fifth of £2000 = £2000 ÷ 5 = £<<2000/5=400>>400.

So, £400 is deducted as tax.

To summarize:
- Onika gives £400 to the charity.
- £400 is deducted as tax.
- £2000 is left after the charity contribution and tax deduction.