X=invested at 10%12000-x=invested at 15% .10x+ (.15)(12000-x)=1440 ;; 12% of the total amount is 12% of $12000. .10x + 1800-.15x=1440
-0.05x=-360x=7200 12000-x=4800 $7200 at 10%=$720$4800 at 15%=$720 That is $12000 earning $1440, and that is 12%
The answer is this:
A. (6,3)
See the attachments for the answer :)
4 tens = 40 and 5 tens = 50 … therefore the number has to be between 40 and 50
So: 40 < x <50 … this says that x is greater than 40 and less than 50
So the possible numbers would be: 41,42,43,44,45,46,47,48,49
Now the number must have 9 ones … which mean the only number would be 49
