Example 3.17 X 4 = ?
Estimate: 3 x 4 = 12
3.17
X 4
28+ 4 ones X 7 hundredths 28 hundredths
40 4 ones x 1 tenth = 4 tenths 40 hundredths
+ 1,200 4 ones X 3 ones = 12 ones = 1,200 hundredths
1,268 hundredths = 12.68
1 Look at the example. Compare the product with the
estimate. Is it reasonable that the product is greater
than the estimate? Explain.

since the airplane is moving with constant speed then the distance travelled can be calculated by x=u*t

in km/h would be:

x=640*3.5=2.240 km

in m/s would be:

u=640 km/h= 640.000 m/h =640.000/ 3600 m/s =177.8 m/s

t= 3.5 h= 3.5 * 3600 s=12.600 s

then x=u*t= 177.8*12.600= 2.240.280 m

it's both, now can you answer my most recent question?

i think it would be 42cm

i do not know the answer

step-by-step explanation: