At the city museum, child admission is $6.30 and adult admission is $9.60. On Sunday, twice as many adult tickets as child tickets were sold, for a total sales of $510.00. How many child tickets were sold that day?

20 child tickets were sold that day.

Step-by-step explanation:

Let x represent the number of child tickets that were sold that day.

Let y represent the number of adult tickets that were sold that day.

On Sunday, twice as many adult tickets as child tickets were sold. It means that

y = 2x

At the city museum, child admission is $6.30 and adult admission is $9.60. The total sales for that day was $510.00. It means that

6.3x + 9.6y = 510- - - - - - - - - - - -1

Substituting y = 2x into equation 1, it becomes

6.3x + 9.6 × 2x = 510

6.3x + 19.2x = 510

25.5x = 510

x = 510/25.5

x = 20

y = 2x = 2 × 20

y = 40

x > 1.3

step by step:

8.5−0.9x> 9.8−1.9x

step 1: simplify both sides of the inequality.

−0.9x+8.5> −1.9x+9.8

step 2: add 1.9x to both sides.

−0.9x+8.5+1.9x> −1.9x+9.8+1.9x

1x+8.5> 9.8

step 3: subtract 8.5 from both sides.

1x+8.5−8.5> 9.8−8.5

1x> 1.3

step 4: divide both sides by 1.

1x/1 > 1.3/1