<h2>
Answer:</h2>
2. 4t
3. 6 + n
4. 6w
5. d - 7
6. 62 + h
7. 20 - y
8. z/4
9. 20 - s
10. 3/5
11. 4s
12. u + v
<h2>
Step-by-step explanation:</h2>
**essentially in all these problems you have to determine the operation that fits each scenario and identify the constant vs. the unknown value. The unknown value is represented by a variable (a, x, y, z, t, d, etc.) and the constant is the given number.**
2. if you buy four packs of pencil with an unknown but same amount in each pack, then you have 4t. 4 TIMES the unknown amount equals the total.
3. you start with 6, your constant and then you ADD the number of pens your friend gave, but you don't know so you replace with the stated variable, n. 6 + n is the answer.
4. Each bag has six apples but you don't know how many bags you bought so if we replace this with the variable w. 6w (the constant always comes before the variable even though w6 = 6w) For example if you bought 2 bags, 6 x 2 = 12, a total of 12 apples.
5. you start with chocolates, but we don't know the number. you eat seven of them, that means from the total number we are "missing" seven. therefore d - 7 accurately describes the scenario.
6. the constant is 62, and we are increasing by something, but we don't know what it is: 62 + h
7. we start with 20 balloons, then we lose an unknown number: 20 - y. We have to SUBTRACT from the total because we "lost".
8. we have an unknown number of fish in an aquarium but we are sure that 1/4 OF that number make up the angelfish population. The word "of" means multiply in mathematical terms so z • 1/4 OR z/4.
9. we have 20 marbles total. out of that number an unknown but represented value are red, "s". the rest are blue. So we will imaginarily take out all the red marbles. This action is SUBTRACTING "s" from 20 and we have only ___ amount of blue marbles left. Therefore the answer is 20 - s.
10. 2/5 OF the class are boys. The remainder are girls. What is 5/5 - 2/5? 3/5. <u>This is the TRICK QUESTION!!</u>
11. A car has 4 wheels each therefore 4 TIMES the total number of cars is the right equation. 4s.
12. If you start with an unknown amount of toys, "u", and you get an unknown amount more, "v", you are adding to your collection therefore the answer is u + v.
Hope these explanations help! There really isn't much more to the concept.