All categories

3 years ago

Noah says to find 20% of a number he divides the number by 5. Is this true explain your answer

Mathematics

1 answer:

Nutka1998 [239]3 years ago

5 0

Answer:

yes

Step-by-step explanation:

note that 20% = $\frac{20}{100}$ = $\frac{1}{5}$

Hence to find 20% of a number, dividing the number by 5 is correct

20% of £30 = $\frac{30}{5}$ = £6

You might be interested in

Use Euler's method with step size 0.2 to estimate y(1), where y(x) is the solution of the initial-value problem y' = x2y − 1 2 y

irina [24]

Answer:

Therefore the value of y(1)= 0.9152.

Step-by-step explanation:

According to the Euler's method

y(x+h)≈ y(x) + hy'(x) ....(1)

Given that y(0) =3 and step size (h) = 0.2.

$y'(x)= x^2y(x)-\frac12y^2(x)$

Putting the value of y'(x) in equation (1)

$y(x+h)\approx y(x) +h(x^2y(x)-\frac12y^2(x))$

Substituting x =0 and h= 0.2

$y(0+0.2)\approx y(0)+0.2[0\times y(0)-\frac12 (y(0))^2]$

$\Rightarrow y(0.2)\approx 3+0.2[-\frac12 \times3]$ [∵ y(0) =3 ]

$\Rightarrow y(0.2)\approx 2.7$

Substituting x =0.2 and h= 0.2

$y(0.2+0.2)\approx y(0.2)+0.2[(0.2)^2\times y(0.2)-\frac12 (y(0.2))^2]$

$\Rightarrow y(0.4)\approx 2.7+0.2[(0.2)^2\times 2.7- \frac12(2.7)^2]$

$\Rightarrow y(0.4)\approx 1.9926$

Substituting x =0.4 and h= 0.2

$y(0.4+0.2)\approx y(0.4)+0.2[(0.4)^2\times y(0.4)-\frac12 (y(0.4))^2]$

$\Rightarrow y(0.6)\approx 1.9926+0.2[(0.4)^2\times 1.9926- \frac12(1.9926)^2]$

$\Rightarrow y(0.6)\approx 1.6593$

Substituting x =0.6 and h= 0.2

$y(0.6+0.2)\approx y(0.6)+0.2[(0.6)^2\times y(0.6)-\frac12 (y(0.6))^2]$

$\Rightarrow y(0.8)\approx 1.6593+0.2[(0.6)^2\times 1.6593- \frac12(1.6593)^2]$

$\Rightarrow y(0.6)\approx 0.8800$

Substituting x =0.8 and h= 0.2

$y(0.8+0.2)\approx y(0.8)+0.2[(0.8)^2\times y(0.8)-\frac12 (y(0.8))^2]$

$\Rightarrow y(1.0)\approx 0.8800+0.2[(0.8)^2\times 0.8800- \frac12(0.8800)^2]$

$\Rightarrow y(1.0)\approx 0.9152$

Therefore the value of y(1)= 0.9152.

4 0

3 years ago

The National Aeronautics and Space Administration (NASA) purchased a new solar-powered battery guaranteed to have a failure rate

Reptile [31]

Answer:

The probability that all three batteries would fail is given as:

= 0.000125

Step-by-step explanation:

Given that the probability of the new battery failing = 1/20 or 0.05,

Therefore, the probability that all three batteries would fail is given as:

= Probability of battery A failing * Probability of battery B failing * Probability of battery C failing

= P(A)*P(B)*P(C)

= 0.05 * 0.05 * 0.05

= 0.000125

5 0

3 years ago

How many solutions are in this equation?

vfiekz [6]

9(x-4)=9x-33

9x-36=9x-33

No solution so b =0

3 0

3 years ago

Read 2 more answers

What is the equation of a line parallel to y=7x-8 that passes through (5,-2)

Wewaii [24]

Answer:

y=7x+8

Step-by-step explanation:

Find the slope of the original line and use the slope-intercept form

7 0

3 years ago

Last summer milo sold water bottles at the park to raise money for his baseball team he made the table below does the table show

evablogger [386]

Answer:

Step-by-step explanation:

For a proportional relationship :

y = kx

Where , k = constant of proportionality

Taking the first set of data:

x = 50 ; y = 10

10 = 50k

k = 10/ 50 = 1/5

Hence, the proportional equation or relation is :

y = 1/5x

Check if this is true for other data points on the data :

Taking the second data point :

x = 85 ; check if y will be 20

From :

y = 1/5x

y = 1/5*85

y = 85/5

y = 17

Since ;

y value from the equation isn't the same as that in the table, then the table does not show a proportional relationship.

4 0

2 years ago