Lawrence has 10 coins in his pocket. one coin is a quarter, and the others are all nickels or dimes. the coins are worth 90 cents. how many nickels and dimes does lawrence having his pocket?

10-1 = 9 dimes and nickels

0.90 - 0.25 = 0.65 worth

N + d = 9

N=9-d

0.05N + 0.10D = 0.65

0.05(9-d) +0.10d = 0.65

0.45 - 0.05d +0.1d = 0.65

0.45 +0.05d = 0.65

0.05d = 0.20

d = 0.20/0.05

d = 4

 4 dimes and 5 nickels

answer:

total cost for tiles and paints is $924.  

step-by-step explanation:

we have been given that a community hall is in the shape of a cuboid. the hall is 40m long 15m high and 3m wide.

the paint will be required for 4 walls and ceiling.

let us find area of walls and ceiling.

therefore, the area of walls and ceiling is 1410 square meters.

given: cost for 10 litre of paint is $10 and 10 litre paint covers 25 square meter. therefore,

therefore, the total painting cost is $564.

tiles will be required for floor. let us find the area of floor.

given: 1m squared floor tiles costs $3. so,

therefore, the total tiles cost is $360.

now let us find combined total cost of tiles and paint.

therefore, the combined total cost of tiles and paint is $924.