A man decides to give his son 1,000 LL. for every math exercise solved properly so as to encourage him to study mathematics, but takes back 500 L. L. if the solution is wrong. After 30 exercises, each has given and received the same amount. How many exercises did the son solve properly?

look, there is 1000 for every right, and 500 for wrong

so if we will take 1000 and plus 2 times 500 (2 wrong, it will be 1000) it will be 3 tasks for be as in the start. so divide 30 at 3, and u will got ten, and in every ten 2 are wrong, and 1 right. so 20 wrong 10 right

step-by-step explanation:

the inequality is:

250c+180g≥950

step-by-step explanation:

let c denotes the number of days in a week   miyoko worked as a cryptographer.

and g denotes the number of days in a week she works as a geologist.

now we are given that she earns $250 for every day she works as a cryptographer,and earns $180 for every day she works as a geologist.

now miyoko's goal is to earn more than $950 this week.

hence, the inequality could be represented as:

250c+180g≥950