One apple and three oranges cost $5.10 and another 5 oranges and one Apple cost $7.50 what is the price of one apple and one orange

$2.7

Step-by-step explanation:

Let the price of one apple be x

and the price of one orange y

Hence ;

One apple and 3 oranges would cost:

x + 3×y = $5.10(1)

One apple and 5 oranges would cost;

x + 5×y = $7.50(2)

Subtracting eqn (1) from (2), we have :

x-x + 5y -3y = 7.5- 5.1

2y = 2.4

y = $1.2

From eqn(1)

x + 3y = $5.10

x= $5.10-3($1.2) = $5.10-$3.6 = $1.5

Hence x=$1.5 and y= $1.2

We are required to find the cost of one apple and one orange, hence :

x+y = $1.5+$1.2= $2.7

2.   2 3/5.

3.   2 1/2.

step-by-step explanation:

6 - 3 2/5

= 6 -   17/5

= 30/5 - 17/5

= 13/5

= 2 3/5 (answer).

5 1/4 - 2 3/4

= 21/4 - 11/4

= 10/4

= 2 1/2 (answer).

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