Mr. Jones lives in City A and drives at a constant speed to City B, which is 400 km 2 of the distance at that same away. On the way back to City A, Mr. Jones drives 5 constant speed. Then, because of rain, he decreases his speed by 20 km/h. The round trip takes 11 hours. How fast did Mr. Jones drive during the rainy part of his trip from City B to City A?​

He traveled at 72km/hr during the rain

Step-by-step explanation:

Question is not well formatted. See comment

Given

--- distance

--- total time

Let his speed from city A till the rain starts on his return trip be

Let his speed from city during the rain be

So:

Required

Calculate

From the question, we understand that; he drives the whole 400 km and 2/5 of 400 km at

The distance covered during this period is:

And the time during this period is:

So, the distance during the rain is:

And the time during the rain is:

So, we have:

--- distance covered before the rain

--- distance covered when raining

---- time spent before the rain

--- time spent in the rain

Speed is calculated as:

Make distance the subject

So:

Recall that:

Make the subject

The expression becomes:

Collect like terms

Solve for

answer:

payment just for service  

→

$

87.12

payment for service including tax

→

$

94.09

explanation:

service only with 20% tip  

→

$

72.6

(

1

+

20

100

)

=

$

87.12

in the opening of the question the word 'service' is associated only with the pretax value.

the closing part of the question asks: how much did she pay for the  

service

−−−−−−  

so technically the answer is  

→

$

72.6

(

1

+

20

100

)

=

$

87.12

however, the intention of the question provider may have been that your answer is to be  

$

87.12

(

1

+

8

100

)

=

$

94.09

to 2 decimal places.

'

payment just for service  

→

$

87.12

payment for service including tax

→

$

94.09

tony b

mar 21, 2017

answer:

trying to explain it another way

explanation:

service charge  

.

→

$

72.60

20% tip  

20

100

×

$

72.60

=

$

14.52

−−−−−−  

←

add

$

87.12

tax  

8

100

×

$

87.12

=

$

6.97

−−−−−  

←

add

$

94.09

related questions

step-by-step explanation:

if you meant, "on the way from (3, 2) to (3, 14):

x does not change; y increases by 12.

ensure that you have copied down this problem correctly.   .