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evablogger [386]

4 years ago

15

Two runners start 30kilometer apart and run toward each other. they meet after 3hours. One Runner runs 2 kilometers per hour fas

ter than the other runner. What rate do they run

1 answer:

joja [24]4 years ago

3 0

Answer:

4 km per hour and 6 km per hour.

Step-by-step explanation:

The combined running rate = 30/3 = 10 km/h.

If one runner's speed = x then the other one's speed is x+2 km/h.

So x + x + 2 = 10

2x = 8

x = 4

So one runs at 4 km/h and the other at 6 km/h.

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Suppose the rate of type II diabetes in 40- to 59-year-olds is 7% among Caucasians, 10% among African-Americans, 12% among Hispa

melomori [17]

Answer:

The overall probability of type II diabetes among 40- to 59-year-olds in Houston is 9.3%.

Step-by-step explanation:

We have these following rates of type II diabetes:

7% among Caucasians

10% among African-Americans

12% among Hispanics

5% among Asian-Americans.

The ethnic distribution of Houston is:

30% Caucasian

25% African-American

40% Hispanic

5% Asian-American

What is the overall probability of type II diabetes among 40- to 59-year-olds in Houston?

$P = P_{1} + P_{2} + P_{3} + P_{4}$

$P_{1}$ is the probability of finding a Caucasian with type II diabetes in Houston. So it is 7% of 30%.

$P_{1} = 0.07*0.30 = 0.021$

$P_{2}$ is the probability of finding an African-American with type II diabetes in Houston. So it is 10% of 25%.

$P_{2} = 0.1*0.25 = 0.0215$

$P_{3}$ is the probability of finding a Hispanic with type II diabetes in Houston. So it is 12% of 40%.

$P_{3} = 0.12*0.40 = 0.048$

$P_{4}$ is the probability of finding an Asian-American with type II diabetes in Houston. So it is 5% of 5%.

$P_{3} = 0.05*0.05 = 0.0025$

$P = P_{1} + P_{2} + P_{3} + P_{4} = 0.021 + 0.0215 + 0.048 + 0.0025 = 0.093$

The overall probability of type II diabetes among 40- to 59-year-olds in Houston is 9.3%.

4 0

4 years ago

How many terms are in the algebraic expression Negative 7 + 12 x 4 minus 5 y 8 + x?

BARSIC [14]

Answer:

Therefore,

There are Four i.e 4 terms in the expression,

$-7+12x^{4}-5y^{8}+x$

Step-by-step explanation:

Algebraic Expression:

An algebraic expression is a mathematical expression that consists of variables, numbers and operations.

Variables with the coefficient is called as Term.
Number is also a term.

Here the Expression is

$-7+12x^{4}-5y^{8}+x$

So,

$-7 = One\ Term\\12x^{4}=Second\ Term\\-5y^{8}=Third\ Term\\x=Fourth\ Term$

In all there are Four i.e 4 terms in the given expressions.

Therefore,

There are Four i.e 4 terms in the expression,

$-7+12x^{4}-5y^{8}+x$

5 0

4 years ago

Read 2 more answers

1/X 1/4=7/12 solve and check solution

liraira [26]

$\frac { 1 }{ x } +\frac { 1 }{ 4 } =\frac { 7 }{ 12 } \\ \\ \frac { 1 }{ x } =\frac { 7 }{ 12 } -\frac { 1 }{ 4 }$

$\\ \\ \frac { 1 }{ x } =\frac { 7 }{ 12 } -\frac { 3 }{ 12 } \\ \\ \frac { 1 }{ x } =\frac { 4 }{ 12 } =\frac { 1 }{ 3 } \\ \\ 3x\cdot \frac { 1 }{ x } =\frac { 1 }{ 3 } \cdot 3x\\ \\ x=3$

6 0

3 years ago

Read 2 more answers

Help help help it is simple one

algol [13]

Answer:

$3^{ -x+3}$

Step-by-step explanation:

We need to simplify out the given exponential expression . The given expression to us is ,

$\rm\implies \dfrac{\dfrac{1}{3}}{3^{x-4}}$

We can use the <u>Law of </u><u>Exponents</u> to simplify the given expression . Recall that ,

$\rm\implies \red{\dfrac{a^m}{a^n}= a^{m-n}}$

Note that , we can write ,

$\rm\implies \dfrac{1}{3}= 3^{-1}$

Therefore our expression becomes ,

$\rm\implies \dfrac{ 3^{-1}}{3^{x-4}}$

Simpify using the Law of Exponents ,

$\rm\implies 3^{ -1 - ( x - 4 )}$

Open the brackets in exponent ,

$\rm\implies 3^{ -1 - x +4 }$

Simplify to get final expression ,

$\rm\implies \boxed{\quad \blue{ 3^{-x+3} \quad}}$

5 0

3 years ago

At a height of about 212 meters, One Shell Square is the tallest building in New Orleans. Marlie is creating a scale model of th

SIZIF [17.4K]

$\bf \begin{array}{ccllll}
building&model\\
\textendash\textendash\textendash\textendash\textendash\textendash&\textendash\textendash\textendash\textendash\textendash\textendash\\
250&1\\
212&x
\end{array}\implies \cfrac{250}{212}=\cfrac{1}{x}$

solve for "x"

3 0

4 years ago