Which of the ratios below is equivalent to 2:3? Select all that apply.

Bogdan [553]

16/14.72=1.08695652174

6 0

3 years ago

Sal was tired of waiting for Amir to show up at their meeting place, so he started running at an average speed of 4.5 mph withou

sergiy2304 [10]

A=-.25+6.7t, s=.75+4.5t when Amir catches up a=s so:

-.25+6.7t=.75+4.5t add .25 to both sides

6.7t=1+4.5t subtract 4.5t from both sides

2.2t=1 divide both sides by 2.2

t=10/22 hr

t≈0.45 hr (to nearest hundredth)

4 0

3 years ago

Read 2 more answers

In the same year. Of the 258 million tons of waste generated 136 million tons ended up in a landfill. What is the percentage of

Assoli18 [71]

Answer: 37 percent of waste is disposed of in some form of a landfill, 8 percent of which is disposed of in sanitary landfills with landfill gas collection systems

The U.S. is the king of trash, producing a world-leading 250 million tons a year—roughly 4.4 pounds of trash per person per day Collectively, out of the 254 million tons of trash Americans can produce in one year, we recycle about 34.3 percent of it. For our average individual, 710.6 pounds are recycled and 1,361.4 pounds of trash are tossed out every year — about the weight of a grizzly bear Every year, U.S. landfills are filled with 139.6 million tons of waste, including 30.63 million tons of food. 26.82 million tons of plastic. 18.35 million tons of paper and paperboard.

don't mark brainiest

3 0

3 years ago

Determine the formula for the nth term of the sequence:<br>-2,1,7,25,79,...

rodikova [14]

A plausible guess might be that the sequence is formed by a degree-4* polynomial,

$x_n = a n^4 + b n^3 + c n^2 + d n + e$

From the given known values of the sequence, we have

$\begin{cases}a+b+c+d+e = -2 \\ 16 a + 8 b + 4 c + 2 d + e = 1 \\ 81 a + 27 b + 9 c + 3 d + e = 7 \\ 256 a + 64 b + 16 c + 4 d + e = 25 \\ 625 a + 125 b + 25 c + 5 d + e = 79\end{cases}$

Solving the system yields coefficients

$a=\dfrac58, b=-\dfrac{19}4, c=\dfrac{115}8, d = -\dfrac{65}4, e=4$

so that the n-th term in the sequence might be

$\displaystyle x_n = \boxed{\frac{5 n^4}{8}-\frac{19 n^3}{4}+\frac{115 n^2}{8}-\frac{65 n}{4}+4}$

Then the next few terms in the sequence could very well be

$\{-2, 1, 7, 25, 79, 208, 466, 922, 1660, 2779, \ldots\}$

It would be much easier to confirm this had the given sequence provided just one more term...

* Why degree-4? This rests on the assumption that the higher-order forward differences of $\{x_n\}$ eventually form a constant sequence. But we only have enough information to find one term in the sequence of 4th-order differences. Denote the k-th-order forward differences of $\{x_n\}$ by $\Delta^{k}\{x_n\}$ . Then

• 1st-order differences:

$\Delta\{x_n\} = \{1-(-2), 7-1, 25-7, 79-25,\ldots\} = \{3,6,18,54,\ldots\}$

• 2nd-order differences:

$\Delta^2\{x_n\} = \{6-3,18-6,54-18,\ldots\} = \{3,12,36,\ldots\}$

• 3rd-order differences:

$\Delta^3\{x_n\} = \{12-3, 36-12,\ldots\} = \{9,24,\ldots\}$

• 4th-order differences:

$\Delta^4\{x_n\} = \{24-9,\ldots\} = \{15,\ldots\}$

From here I made the assumption that $\Delta^4\{x_n\}$ is the constant sequence {15, 15, 15, …}. This implies $\Delta^3\{x_n\}$ forms an arithmetic/linear sequence, which implies $\Delta^2\{x_n\}$ forms a quadratic sequence, and so on up $\{x_n\}$ forming a quartic sequence. Then we can use the method of undetermined coefficients to find it.