All categories

2 years ago

Lily finished a task in 3/4 hour .Ella finished it in 4/5 of time Lily took.How long did Ella take to finish the task?

Mathematics

1 answer:

Zarrin [17]2 years ago

7 0

Time taken by Ella is 0.6 hour

Solution:

Lily finished a task in $\frac{3}{4}$ hour

Ella finished it in $\frac{4}{5}$ of time Lily took

To find: time taken by Ella to finish the task

Let "L" be the time taken by Lily

Time taken by Lily = L = $\frac{3}{4} \text{ hour }$

From given statement,

Time taken by Ella to finish the task is $\frac{4}{5}$ of time Lily took

Therefore,

Time taken by Ella = $\frac{4}{5}$ of time taken by Lily

$\text{ Time taken by Ella } = \frac{4}{5} \text{ of } \frac{3}{4}\\\\\text{ Time taken by Ella } = \frac{4}{5} \times \frac{3}{4}\\\\\text{ Time taken by Ella } = \frac{3}{5}\\\\\text{ Time taken by Ella } = 0.6$

Thus time taken by Ella is 0.6 hour

You might be interested in

What is the other square root of 119 + 120i?

MakcuM [25]

Answer:

$\sqrt{119+120 i}=\pm (12.24+i 4.90)$

Step-by-step explanation:

Given

z = 119 + 120 i

Let $\sqrt{119+120 i}=p+iq$

Squaring both sides

$119+120 i=p^2-q^2+2ipq$

Comparing real and imaginary part

Re(LHS)=Re(RHS)

$119=p^2-q^2$ ...........................(1)

comparing Im(LHS)=Im(RHS)

120=2pq

$q=\frac{60}{p}$

Substitute q in 1

$119=p^2-(\frac{60}{p})^2$

$p^4-119p^2-(68)^2=0$

Let $x=p^2$

$x^2-119x-4624=0$

$x=\dfrac{119\pm \sqrt{119^2+4\times 4624}}{2}$

$x=\frac{119\pm 180.71}{2}$

we take only Positive value because $p^2=x$

x=149.85

$p^2=149.85$

thus $p=\pm 12.24$

$q=\pm 4.90$

thus,

$\sqrt{119+120 i}=\pm (12.24+i 4.90)$

8 0

2 years ago

A 10 foot ladder is leaning against a wall. Call x the distance from the top of the ladder to the ground, and call y the distanc

liq [111]

$-5.3\:\text{ft/s}$

Step-by-step explanation:

We start by applying the Pythagorean theorem to the ladder, with its length L as the hypotenuse:

$L^2 = 100\:\text{ft}^2 = x^2 + y^2$

where x is the vertical distance from the top of the ladder to the ground and y is the horizontal distance from the bottom of the ladder to the wall. Taking the derivative of the above expression with respect to time, we get

$0 = 2x\dfrac{dx}{dt} + 2y\dfrac{dy}{dt}$

Solving for dx/dt, we get

$\dfrac{dx}{dt} = -\left(\dfrac{y}{x}\right)\dfrac{dy}{dt} = -\left(\dfrac{\sqrt{L^2 - x^2}}{x}\right)\dfrac{dy}{dt}$

We know that

$\dfrac{dy}{dt} = 4\:\text{ft/s}$

when x = 6 ft. So the rate at which the top of the ladder is going down is

$\dfrac{dx}{dt} = -\left(\dfrac{\sqrt{100\:\text{ft}^2 - (6\:\text{ft})^2}}{6\:\text{ft}}\right)(4\:\text{ft/s})$

$\:\:\:\:\:\:\:= -5.3\:\text{ft/s}$

The negative sign means that the distance x is decreasing as y is increasing.

5 0

2 years ago

HELP! 15 POINTS! 1 QUESTION!

umka2103 [35]

f(x) = 8x-9

substitute 4 in for x

f(4) = 8(4) -9

f(4) = 32 -9

f(4) =23

6 0

3 years ago

CAN SOMEONE GIVE ME A SUPER SIMPLE ANSWER TO THIS!!??

umka2103 [35]

Answer:

A difference of squares has the following form . Any two perfect squares connected by subtraction can be factored.

It factors to (a+b)(a-b).

Step-by-step explanation:

A binomial is an expression with only terms where at least one is a term with a variable. When we can factor for difference of squares, we can have two variable terms or just one with a constant.

A difference of squares has the following form . Any two perfect squares connected by subtraction can be factored.

It factors to (a+b)(a-b).

6 0

2 years ago

Which statements below correctly describe the relationship shown in the table

Taya2010 [7]

I believe it is d.
Equation is y= 1/2x.
When a number or fraction is next to a variable that means to multiply.
So let’s replace the variable,x, with 6.
If you multiply 1/2 by 6, you get 3.
If you multiply 1/2 by 24 you get 12.
Continue that process to find the other answers

4 0

2 years ago