Question

A building cast a shadow of 12 feet. At the same time a 3 feet yard stick held vertically cast a shadow of 4.5 inches. How tall is the building?

Answer 1

Use ratios...

height of object/length of shadow = height of other object/other length of it's shadow

Answer 2

ok, but I do not understand

Answer 3

Since you don't know height of building, let that be x....

so for building, ratio is x/12
for the other it would 3/4.5

Answer 4

So I multiply now

Answer 5

ya so now cross multiply

Answer 6

set those equal to each other and cross multiply

Answer 7

I am lost

Answer 8

you've got your ratios set up?

Answer 9

yes

Answer 10

ok so now cross multiply:

Answer 11

4.5x=36

Answer 12

hold on

Answer 13

ok

Answer 14

yes

Answer 15

then finish solving for x

Answer 16

Divide by 4.5

Answer 17

right

Answer 18

ok give me a sec

Answer 19

ok

Answer 20

I got 8ft tall

Answer 21

that's right!

Answer 22

well there you go!

Answer 23

Thanks so much

Answer 24

welcome

Answer 25

You're welcome :)

Answer 26

lol

Answer 27

You are good

Answer 28

ty

Answer 29

You like math

Answer 30

no i really dont

Answer 31

I do Haha

Answer 32

lol

Answer 33

hey you know anything bout radiation in Japan?

Answer 34

Can you help me with 1 more?

Answer 35

sure

Answer 36

Just from the news

Answer 37

its for my hw i need to know about the rafdiation stuff

Answer 38

A map uses a scale of 1 centimeter for each 5 kilometer

Answer 39

I can tell you what I have seen

Answer 40

If the distance on a map from City A to city B is 17.5 cm

Answer 41

what is the distance between the cities in kilometers

Answer 42

and in miles

Answer 43

well i dont know about miles

Answer 44

but i can help you with the other thing

Answer 45

There are 2.54 cm in 1 inch and 5280 ft in 1 mile

Answer 46

ok, thanks

Answer 47

so you know that for eveery centimeter it is equal to 5 kilometers

Answer 48

What do you need to know about the radiation?

Answer 49

yes

Answer 50

w8 lemme help you with your stuff then you tell me radiation blah blah

Answer 51

Use ratios again....

cm/km = cm/km or
1/5 = 17.5 cm/x

Answer 52

ok

Answer 53

then cross multiply

Answer 54

yup exactly what he/she said

Answer 55

She :)

Answer 56

oh ok lol

Answer 57

would 1/5 be over 1

Answer 58

no, just leave it as 1/5

Answer 59

How can it be cross multiplied?

Answer 60

1 * x = 5 * 17.5

Answer 61

yea

Answer 62

85

Answer 63

I meant 87.5

Answer 64

Yes, 87.5 km

Answer 65

lol 64 replies!!!!!!!!!!

Answer 66

65

Answer 67

to this question

Answer 68

Ha!

Answer 69

Now to convert 87.5 km to miles?

Answer 70

Convert km to cm, then cm to inches, inches to feet, and feet to miles

Answer 71

I am not good with geometry

Answer 72

there are 1000 meters in one km, so first multiply by 1000

Answer 73

Will that -= the miles

Answer 74

this means 87.5 km = 87,500 m.....
then, there are 100 cm in a meter, so mulitply the above answer by 100 and you'll have the answer in centimeters

Answer 75

so it's 8,750,000 cm

Answer 76

we would g through all the steps to get to the miles, correct?

Answer 77

yes, from cm, you would convert to get inches, then with inches you can get feet, and then feet to miles

Answer 78

You have to be careful though. There are 2.54 cm in 1 inch, so this time you DIVIDE by 2.54

Answer 79

ok

Answer 80

36 inches in 1 ft, so DIVIDE by 36

Answer 81

You would divide 8,750,000 by 36?

Answer 82

no, divide by 2.54 first

Answer 83

ok

Answer 84

then that answer by 36

Answer 85

95691 miles

Answer 86

then last step, 5280 ft in a mile

Answer 87

yes, but don't round the answer until you have divided by 5280

Answer 88

and round answer to however many decimal places you need

Answer 89

I got 18.12 miles

Answer 90

Correct!

Answer 91

Thanks

Answer 92

Hmmmm, that doesn't sound right....let me double check my work :)

Answer 93

NO, that IS right...I was thinking about something else...Sorry :)

Answer 94

ok

Answer 95

Haha, I'm confusing myself....let me check that

Answer 96

I messed you up....so, sorry....there are 12 inches in a foot....OOPS

Answer 97

we used 36.....sorry about that

Answer 98

The radiation in Japan has traveled to some parts of the U.S, through the water. The amount that is in seafood, they say is small, but a lot of places has stopped selling things like fish.