All categories

3 years ago

Priya has completed 9 exam questions. This is 60% of the questions on the exam. How many questions are on the exam?

Mathematics

1 answer:

USPshnik [31]3 years ago

8 0

the whole exam will be 100%, and let's say that's "x" questions, but we also know that 9 is 60% of that so

$\bf \begin{array}{ccll} amount&\%\\ \cline{1-2} x&100\\ 9&60 \end{array}\implies \cfrac{x}{9}=\cfrac{100}{60}\implies \cfrac{x}{9}=\cfrac{5}{3}\implies 3x=45 \\\\\\ x=\cfrac{45}{3}\implies x=15$

You might be interested in

Write the converse of this statement. If 3 - 2x = 13, then x = -5.

stiv31 [10]

Basically your just swapping there positions like so:
if x=-5, then 3-2x=13
Hope this helps! :)

5 0

3 years ago

(9 x 10 ^10) - ( 4x10^10)

Marianna [84]

Answer:

5 * 10^10

Step-by-step explanation:

that's it bro. learn how to do it. then you won't need brainly anymore foo'.

4 0

3 years ago

NASA launches a rocket at t = 0 seconds. Its height, in meters above sea-level, as a function of time is given by h ( t ) = − 4.

Oliga [24]

Answer:

$\displaystyle 1)48.2 \: \: \text{sec}$

$\rm \displaystyle 2)3021.6 \: m$

Step-by-step explanation:

<h3>Question-1:</h3>

so when flash down occurs the rocket will be in the ground in other words the elevation(height) from ground level will be 0 therefore,

to figure out the time of flash down we can set h(t) to 0 by doing so we obtain:

$\displaystyle - 4.9 {t}^{2} + 229t + 346 = 0$

to solve the equation can consider the quadratic formula given by

$\displaystyle x = \frac{ - b \pm \sqrt{ {b}^{2} - 4 ac} }{2a}$

so let our a,b and c be -4.9,229 and 346 Thus substitute:

$\rm\displaystyle t = \frac{ - (229) \pm \sqrt{ {229}^{2} - 4.( - 4.9)(346)} }{2.( - 4.9)}$

remove parentheses:

$\rm\displaystyle t = \frac{ - 229 \pm \sqrt{ {229}^{2} - 4.( - 4.9)(346)} }{2.( - 4.9)}$

simplify square:

$\rm\displaystyle t = \frac{ - 229 \pm \sqrt{ 52441- 4( - 4.9)(346)} }{2.( - 4.9)}$

simplify multiplication:

$\rm\displaystyle t = \frac{ - 229 \pm \sqrt{ 52441- 6781.6} }{ - 9.8}$

simplify Substraction:

$\rm\displaystyle t = \frac{ - 229 \pm \sqrt{ 45659.4} }{ - 9.8}$

by simplifying we acquire:

$\displaystyle t = 48.2 \: \: \: \text{and} \quad - 1.5$

since time can't be negative

$\displaystyle t = 48.2$

hence,

at 48.2 seconds splashdown occurs

<h3>Question-2:</h3>

to figure out the maximum height we have to figure out the maximum Time first in that case the following formula can be considered

$\displaystyle x _{ \text{max}} = \frac{ - b}{2a}$

let a and b be -4.9 and 229 respectively thus substitute:

$\displaystyle t _{ \text{max}} = \frac{ - 229}{2( - 4.9)}$

simplify which yields:

$\displaystyle t _{ \text{max}} = 23.4$

now plug in the maximum t to the function:

$\rm \displaystyle h(23.4)- 4.9 {(23.4)}^{2} + 229(23.4)+ 346$

simplify:

$\rm \displaystyle h(23.4) = 3021.6$

hence,

about 3021.6 meters high above sea-level the rocket gets at its peak?

5 0

2 years ago

What conditional statement is represented by the Venn diagram below

ipn [44]

Answer:

Step-by-step explanation:

It's one of each or not both tho:)

6 0

3 years ago

Read 2 more answers

10>x/3+6 help me please

aleksley [76]

Minus 6 both sides
4>x/3
times3 both sides
12>x

4 0

3 years ago

Read 2 more answers