You need to add the problem you need help with....
Answer:
50 nickels, 20 quarters.
Step-by-step explanation:
System of equations (q = # of quarters, n = # of nickels):
<em>q + n = 70, 0.25q + 0.05n = 7.50</em>
the first equation can be changed to q = 70 - n, so we are able to <em>substitute q with 70 - n</em>.
So, it will look like <em>0.25*70 - 0.25n + 0.05n = 7.50</em>. This can be simplified to <em>0.2n = 10</em>, which means that n = 50.
Knowing that we can solve <em>q + 50 = 70</em>, which means that q = 20.
OOHHH!! I like sci not! Okay, so you take the decimal ( which in this case is at the end: 68000. ) and move it over as many times as needed until it gets in between the, in this case, 6 and 8. ( 6.8000 ). You need to show exactly how many times it was actually moved so you multiply that number time 10^ whatever place. In this question, it'll be to the 4th place because you move the decimal over 4 times. The answer will be 6.80 x 10^4 OR -written in short hand- 6.8x10E4
70 times .9 is 63 so 90 minus 63 is27 so it was $27
