All categories

3 years ago

Pls help me on this math question.I am really confused

Mathematics

1 answer:

Natali5045456 [20]3 years ago

6 0

Answer:

640 m

Step-by-step explanation:

We can consider 4 seconds to be 1 time unit. Then 8 more seconds is 2 more time units, for a total of 3 time units.

The distance is proportional to the square of the number of time units. After 1 time unit, the distance is 1² × 80 m. Then after 3 time units, the distance will be 3² × 80 m = 720 m.

In the additional 2 time units (8 seconds), the ball dropped an additional

... (720 -80) m = 640 m

_____

<em>Alternate solution</em>

You can write the equation for the proportionality and find the constant that goes into it. If we use seconds (not 4-second intervals) as the time unit, then we can say ...

... d = kt²

Filling in the information related to the first 4 seconds, we have ...

... 80 = k(4)²

... 80/16 = k = 5

Then the distance equation becomes ...

... d = 5t²

After 12 seconds (the first 4 plus the next 8), the distance will be ...

... d = 5×12² = 5×144 = 720 . . . meters

That is, the ball dropped an additional 720 -80 = 640 meters in the 12 -4 = 8 seconds after the first data point.

You might be interested in

Amanda exercised for 10 minutes every day in the first week, 20 minutes in the second week, 30 minutes in the third week, and 40

Dominik [7]

Amanda's method is linear because the number of minutes increased by an equal number every week.

7 0

2 years ago

Find the area of the trapezoid.

ss7ja [257]

$\bf \textit{area of a trapezoid}\\\\
A=\cfrac{h(a+b)}{2}~~
\begin{cases}
a,b=\stackrel{bases}{parallel~sides}\\
h=height\\[-0.5em]
\hrulefill\\
a=15.8\\
b=21.8\\
h=11.7
\end{cases}\implies A=\cfrac{11.7(15.8+21.8)}{2}
\\\\\\
A=\cfrac{11.7(37.6)}{2}\implies A=219.96$

4 0

3 years ago

Read 2 more answers

A bus travels at 10 km in 30 minutes. What is the average speed of the bus?

zhannawk [14.2K]

Answer:

20 kph

Step-by-step explanation:

Step 1:

10 : 30 Ratio

Step 2:

60 mins in hour

Step 3:

10 : 30 = x : 60 Equation

Step 4:

30x = 600 Multiply

Step 5:

x = 600 ÷ 30 Divide

Answer:

x = 20

Hope This Helps :)

8 0

2 years ago

Jenny opened a package of screws quickly and many of them spilled on the floor. She needs to organize the fasteners according to

hichkok12 [17]

We have to compare diameters and arrange them in order smallest to greatest

We can see units for option A and B are in square inches so they represents area. So first we will find diameter from area using formula

$A = \pi r^{2}$

so for choice (A) area is given as $4.375 \times 10^{7}$ . So plug this in A place in formula and then solve for radius r

$4.375 \times 10^{7} = \pi r^{2}$

$\frac{4.375 \times 10^{7}}{\pi} = \frac{\pi r^{2}}{\pi}$

$1.393 \times 10^{7} } = r^{2}$

$\sqrt{1.393 \times 10^{7}} = \sqrt{r^{2}}$

3731.76 = r

So screw A will have
$diameter = 2 \times r = 2 \times 3731.76 = 7463.52$ inches

Similarly for choice (E) area is $1.428 \times 10^{1} = 14.28$
so again plug in formula

$A = \pi r^{2}$

$14.28 = \pi r^{2}$

$\frac{14.28}{\pi} = \frac{\pi r^{2}}{\pi}$

$4.5477 = r^{2}$

$\sqrt{4.5477} = \sqrt{r^{2}}$

2.13201 = r

So screw E will have
$diameter = 2 \times r = 2 \times 2.13201 = 4.26402$ inches

So diameters of all screws are as follows:

Screw A: 7463.52 inches
Screw B: 1.5 inches
Screw C: $1\frac{7}{8} = \frac{1\times 8+7}{8} = \frac{15}{8} = 1.875$ inches
Screw D: 0.25 inches
Screw E: 4.26402 inches

Comparing all numbers 7463.52, 1.5, 1.875, 0.25, 4.26402 we can see that smallest number is 0.25, then comes 1.5, then 1.875 and then 4.26402 and then 7463.52

So order from least to greatest will be screw D (0.25), B(1.5), C(1.875), E (4.26402), A (7463.52).

So thats the order D,B,C,E,A and the final answer