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Class 9 Computer Science — Staying safe with other people online

Work out how far something you post really travels once other people pass it on, and follow a fixed set of steps when a message is meant to hurt.

Name: ________________________

  1. 1.A message was sent to some number of people to begin with, and every one of them sent it on to 6 more. Altogether 91 people besides the sender have seen it. How many people was it sent to at the start?

  2. 2.A message arrives that was written to hurt you. Sort each of these by whether the four steps allow it.

    Groups: The four steps allow this · The four steps do not allow this

    • Tell a teacher you trust
    • Block the sender once a copy has been kept
    • Reply to say that it was unfair
    • Pass the message on to your friends to see what they think
    • Delete the message straight away so you do not have to see it
    • Take a picture of the message before doing anything else

  3. 3.In the four steps, keeping a copy comes before blocking the sender. Why that way round?

    • a) Because blocking can take the message away with it
    • b) Because blocking somebody tells them that you have kept a copy
    • c) Because blocking the sender also blocks the adult you are going to tell
    • d) Because the copy has to be made on the same day as the message arrived

  4. 4.You post something to 60 people. One in every 4 of them passes it on to 8 people each. How many people besides you have seen it?

  5. 5.There are two things another person online can do that a computer on its own cannot. One is passing your words on to people you never chose. What is the other?

    • a) Storing a copy of a message for years
    • b) Sending the same message to many people at once
    • c) Reading a message faster than it was typed
    • d) Being somebody other than who they say they are

  6. 6.In each of these, you send something to a group and every person in that group sends it on to some number of others. Match each one to how many people besides you have seen it.

    • Sent to 6, each sending it to 5
    • Sent to 10, each sending it to 3
    • Sent to 7, each sending it to 3
    • Sent to 5, each sending it to 11
    • Sent to 15, each sending it to 4
    • 40
    • 28
    • 60
    • 75
    • 36

  7. 7.A message goes to 9 people. Every one of the 9 sends it to 4 more, and every one of those sends it to 3 more. How many people besides you have seen the message by then?

  8. 8.In each of these you send a post to a group and every person in that group passes it on. Put them in order of how many people besides you end up seeing the post, fewest first.

    • To 8 people, each passing it to 4
    • To 5 people, each passing it to 3
    • To 30 people, none of them passing it on
    • To 3 people, each passing it to 20

Answer key — Class 9 Computer Science — Staying safe with other people online

  1. 1. 13
  2. 2. Take a picture of the message before doing anything else → The four steps allow this; Reply to say that it was unfair → The four steps do not allow this; Block the sender once a copy has been kept → The four steps allow this; Pass the message on to your friends to see what they think → The four steps do not allow this; Tell a teacher you trust → The four steps allow this; Delete the message straight away so you do not have to see it → The four steps do not allow this
  3. 3. a) Because blocking can take the message away with it
  4. 4. 180
  5. 5. d) Being somebody other than who they say they are
  6. 6. Sent to 6, each sending it to 5 → 36; Sent to 10, each sending it to 3 → 40; Sent to 7, each sending it to 3 → 28; Sent to 5, each sending it to 11 → 60; Sent to 15, each sending it to 4 → 75
  7. 7. 153
  8. 8. 1. To 5 people, each passing it to 3 2. To 30 people, none of them passing it on 3. To 8 people, each passing it to 4 4. To 3 people, each passing it to 20