Khaya is delivering groceries to his mother who stays 8km from the shop. How long will it take him to cover this distance if he drives at an average speed of 65km/h? Give your answer rounded to the nearest minute.

7.38 minutes

Step-by-step explanation:

Given

Distance= 8km

speed = 65km/h

Time=?

From physics,

Speed= distance/ time

Then substitute the values to find time

65= 8/ time

Time= 8/65

=0.1231 hrs

To Convert to minutes

1hr= 60 mins

0.1231 hrs = X minutes

Cross multiply, we have

X minutes=( 0.1231 × 60)/1

= 7.38 minutes

Hence, it takes 7.38 minutes for him to cover this distance

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places