##### Combinatorics: comprobación de requisito previo

Enseñamos conceptos difíciles con las palabras más simples posibles. Vamos a corroborar que conozcas los términos y las ideas que se necesitan. Este curso es el correcto si obtienes al menos 80% en esta prueba, pero menos del 70 % de la place-out test

Tiempo restante:

10:00

1.

If $$a = 2^b c$$ and $$b = 3$$ and $$c = 5,$$ what is $$A?$$

$$13$$

$$30$$

$$40$$

$$45$$

$$256$$

2.

Calculate:

$\frac{6 \times 5 \times 4}{3 \times 2 \times 1}$

$$\displaystyle \frac{5}{2}$$

$$15$$

$$20$$

$$80$$

$$720$$

3.

All but one of these rings of 6 beads can be obtained from the others by rotating or flipping over the ring. Which is the unusual one?

4.

When buying a certain model of phone, there are $$3$$ colors to choose from, and $$3$$ different amounts of storage to choose from. How many different combinations are there for that phone model?

$$6$$

$$9$$

$$27$$

$$64$$

$$720$$

5.

Jenny has $$3$$ skirts, $$2$$ pants, and $$4$$ shirts. How many ways can she create an outfit with one of the shirts, and either a skirt or pant?

$$8$$

$$9$$

$$12$$

$$20$$

$$24$$

6.

Everybody in a certain middle school takes French, Spanish, or both. The French teacher has a total of $$90$$ students, and the Spanish teacher has a total of $$110$$ students. There are $$20$$ students in both languages. How many students are at the school?

$$180$$

$$190$$

$$200$$

$$210$$

$$220$$