Family Math Studio · Lesson guide Guía de la lección

Unit 2, Lesson 8: Describe Data Using the Mean

Standard 6.DS.4

What students are learning Qué aprenden

Key idea: The mean (or average) is what each value would be if the total were shared equally. To find it, add all the numbers, then divide by how many numbers there are: mean = total ÷ how many numbers.Idea clave: La media (o promedio) es lo que valdría cada dato si el total se repartiera en partes iguales. Para hallarla, suma todos los números y luego divide entre cuántos números hay: media = total ÷ cuántos números hay.

Words to know Palabras clave

Mean Media: Add all the numbers, then divide by how many.; Suma todos los números y divide entre cuántos hay.
Average Promedio: The amount each one gets when the total is shared equally.; Lo que recibe cada uno si el total se reparte igual.
Measure of center Medida de centro: One number that tells what is typical.; Un número que dice qué es típico.
Balance point Punto de equilibrio: The point where the data evens out. It is the mean.; El punto donde los datos quedan parejos. Es la media.
Data set Conjunto de datos: All the values that were collected.; Todos los valores que se reunieron.
Target mean Media objetivo: The mean you want to reach.; La media que quieres alcanzar.
Target total Total objetivo: The total the data must add up to.; El total al que deben sumar los datos.

Sentence starters Frases para empezar

I know ___ because ___.

First, I ___. Then, I ___.

The answer is ___, so ___.

How we did it in class today Cómo lo hicimos hoy en clase

Miguel's 4 days of earnings are shown with counters. When I combine all of the counters, there are 60 of them, which means Miguel earned $60 in all.
Now I redistribute the 60 counters equally among the 4 days. Each of the 4 groups ends up with 15 counters.
The arithmetic does exactly the same thing: I find the total, 60, and divide it by the number of days, 4. So 60 ÷ 4 = 15.
We can use $15 to describe Miguel's typical daily earnings. That leveled value is the mean.

Play with today's math Jueguen con las matemáticas

Interactive Lesson Model — This is the exact same interactive tool your student used in class today. Change the numbers and watch what happens!

Modelo interactivo de la lección — Esta es la misma herramienta interactiva que su estudiante usó en clase hoy. ¡Cambie los números y observe qué sucede!

Works on a phone, a tablet, or a computer. Nothing to install, nothing to sign in to.

Try this together Inténtenlo juntos

Pick one question to talk about. You don't need to do them all!

Leo read 9, 15, 11, and 17 pages on four nights. What is the mean number of pages he read each night?

Check the answer

The answer is: 13

Take-home sheet Hoja para llevar a casa

Lesson 2.8: Print the sheet (PDF) · Answers and talk notes (PDF) · Edit it (Word)

Lección 2.8: Imprimir la hoja (PDF) · Respuestas y notas para conversar (PDF) · Editarla (Word)

If they get stuck... Si se traban...

Watch out for this: The most common mistake with the mean is adding correctly and then dividing by the wrong number — or not dividing at all. Students report the total (for 8, 10, 6, 12 they say the mean is 36) or they divide by a count that does not match the data, such as dividing a 4-value total by 5, or skipping a zero when counting the values. Before you finish, do two things: count the values in the data set out loud, and check that your mean lands between the smallest and largest value. A mean of 36 for data that never goes above 12 is impossible.

Try asking: "Can you show me how you got that? Did we miss a step?"
Pregunte: «¿Puedes mostrarme cómo lo hiciste? ¿Nos saltamos algún paso?» Hablar de las matemáticas en voz alta ayuda mucho.