Problems

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Found: 8

Between them, Jennifer and Alex shared the money they made from running a lemonade stand. Jennifer thought: “If I took \(40\%\) more money then Alex’s share would decrease by \(60\%\)”. How would Alex’s share of the profits change if Jennifer took \(50\%\) more money for herself?

A field that will be used to grow wheat has a rectangular shape. This year, the farmer responsible for this field decided to increase the length of one of the sides by \(20\%\) and decrease the length of another side by \(20\%\). The field remains rectangular. Will the harvest of wheat change this year and, if so, then by how much?

After a circus came back from its country-wide tour, relatives of the animal tamer asked him questions about which animals travelled with the circus.

“Where there tigers?”

“Yes, in fact, there were seven times more tigers than non-tigers.”

“What about monkeys?”

“Yes, there were seven times less monkeys than non-monkeys.”

“Where there any lions?”

What is the answer he gave to this last question?

If a salary is first increased by 20%, and then reduced by 20%, will the salary paid increase or decrease as a result?

During the year, the price for a strudel were twice raised by 50%, and before the New Year they were sold at half price. How much does one strudel cost now, if at the beginning of the year it cost 80 pence?

A council of 2,000 deputies decided to approve a state budget containing 200 items of expenditure. Each deputy prepared his draft budget, which indicated for each item the maximum allowable, in his opinion, amount of expenditure, ensuring that the total amount of expenditure did not exceed the set value of \(S\). For each item, the board approves the largest amount of expenditure that is agreed to be allocated by no fewer than \(k\) deputies. What is the smallest value of \(k\) for which we can ensure that the total amount of approved expenditures does not exceed \(S\)?

In the gymnasium, all students know at least one of the ancient languages – Greek or Latin, some – both languages. 85% of all children know the Greek language and 75% know Latin. How many students know both languages?

Before the start of the Olympics, the price of hockey pucks went up by 10%, and after the end of the Olympics they fell by 10%.

When were the pucks more expensive – before the price rise or after the fall?