Joaquin invirtio su dinero a 12% y a 15% obteniendo unos intereses de $3000. si las cantidades que invirtio hubieran sido intercambiadas, habria tenido un retorno de $2940 .cuanto dinero invirtio a 15%?

$12,000

Explanation:

We know that:

0.12A + 0.15B =  $3000

If the amounts were inverted:

0.12B + 0.15A = $2940

Solving the system of equations:

0.12A + 0.15B =  $3000

0.12B + 0.15A = $2940

The solutions are:

A = 10,000

B = 12,000

So Joaquin invested 12,000 at 15%.

where is the quiz

in my life i wake up get ready for school then i eat breakfast similar to maarit but i do not need to feed chickens or do anything else in the morning. once i am at school i study many different subjects and like maarit my favorite subject is math. then i go home like maarit i do my homework. then unlike maarit i do all my chores right after i do my homework. then i eat dinner and watch t.v until i go to bed. then i wake up and repeat the process once again until the weekend. on the weekend i do nothing i don’t go anywhere with my father i just relax