Gary and Ginger decide to place $\$ 10,000$ of their savings into investments. They put some in a money market account earning $3 \%$ interest, some in a mutual fund that has been averaging $7 \%$ a year, and some in a stock that rose $10 \%$ last year. If they put $\$ 3000$ more in the money market than in the mutual fund and the mutual fund and stocks have the same growth in the next year as they did in the previous year, they will earn $\$ 540$ in a year. How much money did they put in each of the three investments?