Please help soon! Unit test :P

Certain items are purchased jointly. If each person pays 8 coins, the surplus is 3 coins, and if each person gives 7 coins, the

Karo-lina-s [1.5K]

Answer:

7 people purchase the items and they used 53 coins

Step-by-step explanation:

Let x represent the number of people.

Let y be the number of coins needed to purchase the items.

If each person pays 8 coins, the surplus is 3 coins. This is illustrated below:

8x = y + 3 (1)

if each person gives 7 coins, the deficiency is 4 coins. This is illustrated below:

7x = y — 4 (2)

Solving by elimination method: subtract equation(2) from equation (1). This is illustrated below:

8x = y + 3 (1)

— (7x = y — 4) (2)

x = 7.

Next, Substituting the value of x into any of the equation to obtain y. In this case I will be using equation 1 as illustrated below:

8x = y + 3 (1)

8(7) = y + 3

56 = y + 3

Collect like terms

y = 56 — 3

y = 53

Therefore, 7 people purchase the items and they used 53 coins

7 0

3 years ago

For each problem, identify any important quantities. If it's a known quantity, write the

Tema [17]

Answer:

We have the problem:

"Clare is in charge of getting snacks for a road trip with her friends and her dog. She has

$35 to go to the store to get some supplies. The snacks for herself and her friends cost

$3.25 each, and her dog's snacks costs $9 each."

In this situation we have two variables:

X = number of snacks for herself and her friends that she buys. Each one of these costs $3.50

Y = number of snacks for her dog that she buys. Each one of these costs $9.

The total cost, in this case, can be written as:

X*$3.50 + Y*$9

And we know that she has $35 to spend, so she can spend $35 or less in the store, then we have the inequality:

X*$3.50 + Y*$9 ≤ $35

Where we defined all the quantities in the inequality.

4 0

3 years ago

A batch of 20 semiconductor chips is inspected by choosing a sample of 3 chips. Assume 10 of the chips do not conform to custome

Hatshy [7]

Answer:

A batch of 20 semiconductor chips is inspected by choosing a sample of 3 chips. Assume 10 of the chips do not conform to customer requirements.

a) Number of different samples = 20C3 = $\frac{20!}{3!(17!)}$ =1140

b) 2 good and one bad chip

Number of samples = 10C2 * 10C1 = 45 * 10 =450

c) 2 good 1 bad + 1 good 2 bad + 3 bad

Number of samples = 10C2 * 10C1 + 10C1 * 10C2 + 10C3

= $450+450+120=1020$

6 0

3 years ago

Knitting a scarf. On average she can knit 2 mm in 35 minutes. Express this as a rate in mm/min

Natali5045456 [20]

Answer:

she can knit 1mm/17.5min or she can knit 1mm in 17 minutes and 30 seconds.

8 0

2 years ago

En un día de temporal de lluvia el meteorólogo dijo en las noticias que la probabilidad de que lloviera ese día era del 70%. ¿Qu

drek231 [11]

Answer:

Vamos a definir:

100% probabilidad de lluvia = Es seguro que ese día va a llover.

0% probabilidad de lluvia = Es seguro que ese día no va a llover.

Ahora, los valores intermedios admiten una dualidad, es decir, es posible que llueva o que no.

Particularmente en el caso del 70% significa que:

Si tenemos un dado de 10 caras, con los números {1, 2, 3, 4, 5, 6, 7, 8, 9, 10}

Y lo tiráramos, los resultados {1, 2, 3, 4, 5, 6, 7} indicarían que llueve.

Los resultados {8, 9, 10} indicarían que no llueve.

Entonces es mas probable que llueva, pero la probabilidad de que no llueva no es despreciable.

5 0

3 years ago