Susan purchased some municipal bonds yielding 7% annually and some certificates of deposit yielding 9% annually. if Susan's investment amounts to $19,000 and the annual income is $1,590, how much money is invested in bonds and deposits?

1 Answer
Jun 30, 2018

Certificates of deposits #=$.13000#
Bonds #=$.6000#

Explanation:

Susan buys bonds worth #=$.x#
She buys certificates of deposits worth #=$.y#

Yield from bond #=x xx 7/100=(7x)/100#
yield from certificates #=y xx 9/100=(9y)/100#

Then,

#x+y=19000# --------(1)
#(7x)/100+(9y)/100=1590# Multiplying both sides by 100, we get

#7x+9y=159000# -----(2)

Solving equation(1) for #x#, we get #x=19000-y#

Substitute #x=19000-y# in equation (2), we get

#7(19000-y)+9y=159000#

#133000-7y+9y=159000#

#133000+2y=159000#

#2y=159000-133000=26000#

#y=26000/2=13000#

#y=13000#

Certificates of deposits #=$.13000#

Substitute #y=13000# in equation (1)

#x+13000=19000#

#x=19000-13000=6000#

Bonds #=$.6000#