Answer:
10.98 days is 10.98/3.66 = 3 half life periods and half of the mass is lost at each half life. You can do this in your head. I have!!
Step-by-step explanation:
The quadratic formula is the result of completing the square for ax^2+bx+c=0 when a,b, and c are unknown values. This result is:
x=(-b±√(b^2-4ac))/(2a), we have x^2-x-2=0 so
x=(1±√(1+8))/2
x=(1±√9)/2
x=(1±3)/2
x=-1 and 2
Answer:
Answer to question 1: The apple juice costs less because it costs 16 cents per ounce and the orange juice costs 21 cents per ounce
Answer to question 2: 10.12+5.33=15.45 22.31 - 15.45 = 6.86 so joe has $6.86 left
Step-by-step explanation:
1.)
Old Number:35
New Number:45
Now, subract the new number(45) from the old number. (35)
45-35 is 10. Now divide the old number (35) by 10.
You'll get 3.5. 3.5%, increase is the answer for #1.
2.) Old: s (students)
New: 36,750
Do 100+5 (Addition because we do not know what the old number is.) 100+5 is 105. Move decimal over twice and you get 1.05. Multiply 36,750 by 1.05.
There were 38,587.5 kids last year.
3.)Since the discount is 15% off, do 100-15=85. Now, move the decimal over from the percent, and that makes that .85. Now multiply 50x.85. You get 42.5, or $42.50. Now the coupon is 10%, So subtract 100-10, giving you 90. Now move the decimal over. .90. Multiply 42.5 (or 42.50) by .90. You get 38.25. You do have enough money.
4.) Subtract 100-15, giving you 85. Move decimal over from percent. .85.
Now you would multiply .85 times k. B should be the answer.