The ratio of seventh graders to eighth graders at junior high school is 9:10. If there is 90 eighth graders, how many seventh graders would be there?

81

Step-by-step explanation:

To find the base unit of the ration, divide 90 by 10, which is 9. Then multiply 9 (the base unit) by 9 (the ratio of the seventh graders) and that equals 81

.there can be infinite values of m and n that can satisfy the above equation. for each value of m of m or n. there maybe infinite sets of solution for the above

step-by-step explanation:

let x be the money she spent so that she can earn the free t-shirt.

since, she already spent $112.49

⇒

also, as per the statement: jennifer must spend $250 or more in order to qualify for a free t-shirt at the store.

then,

we have an inequality i.,e

subtract 112.49 from both sides we get;

therefore, $137. 51 more money does jennifer need to spend so that she can earn the free t-shirt