Question

Mathematics

2 answers:

GalinKa [24]3 years ago

8 0

Answer:

3 hrs

Step-by-step explanation:

Thinking process:

Time taken by Sam = 4 hours

Time taken by Dave = 2 hours

Raking the lawn together will take them half the time each takes, so:

Sam = $0.5*4$

= 2 hrs

Dave = $0.5 * 2$

= 1 hr

Adding the hours gives = 2 + 1

= 3 hrs

Alika [10]3 years ago

3 0

Answer:

1 hr 15 min

or...

1.25 hrs

Step-by-step explanation:

Sam = 1/4 job = 1 hr

Dave = 1/2 job = 1 hr

1/4 +1/2 = 3/4

3/4 in one hour.

Thus they would take 1.25 hours to do the job together.

You might be interested in

If one chocolate bar makes three snores how many bars will you need to purchase to make 26 smores

lions [1.4K]

26 ÷ 3 = 8.6667

you need to purchase 9 chocolate bars to make 26 smores

6 0

3 years ago

According to Descartes's rule of sign, how many possible positive and negative roots are there for the equation

damaskus [11]

<h2>Descartes Rule of Sign</h2><h3>Answer:</h3>

There are $3$ Real Roots for the Equation

<h3>Step-by-step explanation:</h3>

According to Descartes Rule of Sign, The maximum number of real roots a polynomial equation has is the number of times the sign of term changes from a higher power term to a lower power term.

In the given equation, $0=-4x^6-3x^5+2x^2-4x+1$ , we can already see that from $\red -4x^6$ to $\red -3x^5$ we can see that the sign didn't change so there might be no real roots. From $\red -3x^5$ to $\blue +2x^2$ , we can see that the signs change so we now know that there might be $1$ real root for equation. From $\blue +2x^2$ to $\red -4x$ , the signs changed so there might be $2$ real roots. From $\red -4x$ to $\blue +1$ , it changed again so there might be $3$ real roots. There are no other term with lesser power to compare for $\blue +1$ so we are left with $3$ real roots.