Answer:
- Josh's book lands first
- Ben's lands about 0.648 seconds later
Step-by-step explanation:
Using the given equation for v=60 and s=40, the height of Ben's book is ...
h(t) = -16t² +60t +40
We want to find t when h(t) = 0, so we're looking for the solution to ....
0 = -16t² +60t +40
Using the quadratic formula, we find the positive value of t to be ...
t = (-60 -√(60² -4(-16)(40)))/(2(-16)) = (15 +√385)/8 ≈ 4.3277
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Similarly, the height of Josh's book is ...
0 = -16t² +48t +40
t = (-48 -√(48² -4(-16)(40)))/(2(-16)) = (12 +√304)/8 ≈ 3.6794
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The time before Josh's book lands is shorter by ...
4.3277 -3.6794 ≈ 0.6482 . . . . . seconds
Josh's book reaches the ground first, by about 0.648 seconds.
Answer:
7/30
Step-by-step explanation:
We are given that Seven-ninths (7/9) of the pencils in a box are yellow and three-tenths (3/10) of the yellow pencils are sharpened.
To find the fraction that represents sharpened yellow pencils, we find the product of the the fraction of yellow pencils and the fraction of yellow pencils that are sharpened.
That is:
=> (7 / 9) * (3 / 10)
=(7 * 3) / (9 * 10)
= 21 / 90
= 7 / 30
7/30 represents the fraction of sharpened yellow pencils.
It will take about 16.66 months for the investment to double.
Hope this helps.
Answer:
17.9
Step-by-step explanation:
Answer:
The correct option is the last one (0,84 grams, because (5.04 × 1.67) × (10^23 x 10^-24) = 8.4168 x 10^-1))
Step-by-step explanation:
The first step is to think that you have to multiply the number of atoms for the weight of each atom.
When you work with scientific notation, you should solve the operation for numbers and for the ten base. In this case you solve 5.04 x 1.67 and then the product of the ten bases. For this product you have to sum the exponents of the ten base 23 + (-24) = -1.
Summarizing.... 5.04 x 10^23 x 1.67 x 10^-24 = (5.04 x 1.67) x (10^23x10^-24) ⇒ 5.04 x 10^23 x 1.67 x 10^-24 = 8.4168 x 10^-1
⇒ 5.04 x 10^23 x 1.67 x 10^-24 = 0,84168.
