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3 years ago

Yesterday, 4/7 of the 210 students in a contest gave their speeches. How many students gave their speeches?

Mathematics

1 answer:

Elenna [48]3 years ago

6 0

Answer:

120.

Step-by-step explanation:

210 * 4/7

= 30 * 4

= 120.

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Which of the following graphs best represents f(x) = 3 sin 4x + 2?

Lesechka [4]

The graph for
f(x) = sin x
is a sinusoidal graph with the origin as the middle point and the value increases up to the maximum point before going down crossing the x-axis and reaching the minimum point before increasing again until it crosses the x-axis. The graph continues as a wave on both sides indefinitely.
f(x) = 3 sin 4x
has an amplitude of 3 or the highest point is 3 and a period of
Period = 2π/4 = π/2
f(x) = 3 sin 4x + 2
the graph is shifted 2 points upward.

5 0

3 years ago

Sales tax in Rally County is 8%. What would the amount of tax be on a $50 restaurant bill? Express your answer in the form of a

lesantik [10]

54.00
50x4%=4
50+4=54

3 0

2 years ago

HELP ME PLSSSSSSSSSSS

Bezzdna [24]

Answer:

Option H, 120 units

Step-by-step explanation:

Total rectangle area:

width x length

10 units x 24 units = 240 units

Area of 1 shaded traingle:

A = (height) x (width) / 2

A = (12 units) x (10 units) / 2

A = 120 units / 2

A = 60

Now mutiple A by 2 since we have two shaded regions

60 x 2 = 120

Subtract the entire rectangle area with the shaded area to get the unshdaed area

240 units - 120 units = 120 units

8 0

2 years ago

Keisha bought cups of coffee and bagels for the people in her office. Each bagel cost $2 and each cup of coffee cost $1.50. Keis

-Dominant- [34]

Answer:

The number of bagels is 11 and the cups of coffee is 12.

Step-by-step explanation:

Given:

Keisha bought cups of coffee and bagels for the people in her office. Each bagel cost $2 and each cup of coffee cost $1.50.

Keisha spent a total of $40 to buy 23 items.

Now, to find the number of cups of bagels and coffee.

As given in question:

Let $x$ represent the number of bagels.

And $y$ represent the number of cups of coffee.

So, the total number of items:

$x+y=23$

$x=23-y$ ......(1)

Now, the total money spent on items:

$2x+1.50y=40$

Substituting the value of $x$ from equation (1):

$2(23-y)+1.50y=40$

$46-2y+1.50y=40$

$46-0.50y=40$

Subtracting both sides by 46 we get:

$-0.50y=-6$

Dividing both sides by -0.50 we get:

$y=12.$

The number of cups of coffee = 12.

Now, to get the number of bagel we substitute the value of $y$ in equation (1):

$x=23-y$

$x=23-12$

$x=11.$

The number of bagels = 11.

Therefore, the number of bagels is 11 and the cups of coffee is 12.

6 0

3 years ago

A rock outcrop was found to have 95.82% of its parent U- 238 isotope remaining. Approximate the age of the outcrop. The half-lif

mixer [17]

Answer:

A) 277 million years

Step-by-step explanation:

Here, decay of U-238 is first order reaction. (since most of the nuclear decays are first order).

so, the equation t = $\frac{1}{k}$ × ln( $\frac{A(0)}{A}$ )

where, t = time from start of reaction

k = reaction constant

A(0) = initial concentration; A = present concentration.

⇒ 4.5 billion = 4500 million years = $\frac{1}{k}$ × ln2.

Now, given 95.82% of parent U-238 isotope is left.

⇒ t = $\frac{1}{k}$ × ln( $\frac{A(0)}{A}$ )

t = $\frac{4500}{ln2}$ × ln( $\frac{100}{95.82}$ )

⇒ t ≅ 277 million years.

5 0

2 years ago