Math word problem

Question

Pierre inherited $120,000 from his uncle and decided to invest the money. He put part of the money in a money market that earns 2.2% simple interest. The remaining money was invested in a stock that returned 6% in the first year and a mutual fund that lost 2% in the first year. He invested $10,000 more in the stock than in the mutual fund, and his net gain for 1 year was $2820. Determine the amount invested in each account. 

Answer 1

X+Y+Z = 120000

Y = Z+10000

0.022X + 0.06y - 0.02Z = 2820

X+(Z+10000) + Z = 120000

0.022X + 0.06(Z+10000) - 0.02Z = 2820

X + 2Z = 110000

0.022X + 0.06Z + 600 - 0.02Z = 2820

0.022(110000 - 2Z) + 0.06Z + 600 - 0.02Z = 2820

2420 - 0.044Z + 0.06Z + 600 - 0.02Z = 2820

3020 - -0.004z = 2820

0.004z = 200

z=50000

y=60000

x=10000