Find three consecutive whole numbers such that the sum of the squares of the numbers is equal to 869.

Numbers are: 16, 17. and 18

Step-by-step explanation:

You can estimate it very quickly.

Divide the sum by 3:

869/3 = 289 2/3

That just be close to the square of the middle number. Square root of that is 17.0195... The numbers must be 16 17 18.

Work out he square to verify that.

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