£10,000 at 3% would only give you £25 per month.
But you don't get any interest on the first £1,000.
You get 1% interest on the £1,000 between £1,000 and £2,000, which is £0.83
You get 2% on the £1,000 between £2,000 and £3,000, which is £1.67.
You get 3% on the remaining £7,000, which is...