# Solve the word problem (pls. use the recommended format: given, req’d, solution,checking) Martin Fernandez put part of his money into a bank and...(continued...) invested another half of it in...

Solve the word problem (pls. use the recommended format: given, req’d, solution,checking)

Martin Fernandez put part of his money into a bank and...

(continued...)

invested another half of it in bonds. The bank pays 5% interest. The bonds pay a 7% return. How much money did he invest in each vehicle, if his annual income from the bonds was P600 more than the interest from the bank?

rcmath | Certified Educator

Let P be the orignal amount Martin had.

Given:      Bank                       Bond

Income      5%                         7%

Amount     \$P/2                        \$P/2
invested

Income      \$x                            \$ x+600

Equations:Interest (income)=rate x principal

Bank  `5/100*P/2=x=>[5P]/200=x`

Bonds `7/100*P/2=x+600=>[7P]/200=x+600`

Let solve the system by substitution

`[7P]/200=[5P]/200+600=>` Subtract 5p/200 from both sides

`[2P]/200=600=>P/100=600=>P=60,000`

Answer: He invested \$30,000 in each.

Check: Bank  `5/100*30,000=1500`

Bond `7/100*30,000=2100`

1500+600=2100 correct.