Remember: Binary has two states, on and off, written as one and zero. More switches make more patterns, and patterns can stand for anything.
Read and answer
Read the story, then answer.
The lamps across the laneMina and Teo lived in houses that faced each other across a little lane. It was bedtime, and Mina had a secret to tell. Her desk lamp was either on or off, and Teo could see it from his window. They agreed that lamp on would mean yes, and lamp off would mean no. But yes and no made only two messages. So Mina added a second lamp, and now she could make four patterns. A third lamp made eight patterns, because every new lamp doubles the patterns. Five lamps make thirty-two patterns, which is plenty for every letter of the alphabet. Mina sent a word letter by letter, and Teo wrote each one down. Computers work the same way, with tiny switches that are on or off. On is written as one and off as zero, and that is binary.
1
Look at the lamps. On is written 1 and off is written 0. How is this written?
110101011
2
Two lamps can make four patterns. What goes in the empty box for both lamps on?
100111
3
One lamp can make different patterns.
4
In binary, on is written as zero.
TrueFalse
5
Mina needs a pattern for each of the 26 letters of the alphabet. How many lamps are enough?
4 lamps5 lamps3 lamps
6
Every new lamp doubles the number of patterns.
TrueFalse
Match, order and fix
7
Join each number of lamps to the patterns it can make.
1one lamp
2two lamps
3three lamps
4four lamps
5five lamps
A4 patterns
B8 patterns
C2 patterns
D32 patterns
E16 patterns
8
Circle everything that has only two states.
🔌a light switch🎚️a volume dial🪙a coin on the table🎨a box of paints❔a yes or no answer
9
Put what Mina and Teo did in order.
Five lamps make 32 patterns, plenty for the letters
Lamp on means yes, and lamp off means no
A third lamp makes eight patterns
Mina adds a second lamp, for four patterns
Mina sends a word, and Teo writes each letter down
10
Teo says two lamps make eight patterns. What is the mix-up to fix?
Two lamps make four patterns, and three lamps make eightTwo lamps make two patternsTwo lamps make sixteen patterns
11
Mina has four lamps, and she adds a fifth. How many MORE patterns does she get?
32162
12
With a grown-up, flip a coin 3 times. Write heads or tails each time.
13
Draw three lamps: the first on, the second off, the third on. Write the ones and zeros under them.
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Answer key · Set A
Mina and Teo's lamps
1101 Lamp 1 is on (1), lamp 2 is off (0) and lamp 3 is on (1), so it is written 101.
211 Both lamps are on, so both digits are 1.
32 One lamp is either on or off, which makes two patterns.
4False On is written as one and off is written as zero.
55 lamps Four lamps make only 16 patterns, but five lamps make 32, which is plenty for 26 letters.
6True One lamp gives 2 patterns, two lamps give 4, and three lamps give 8.
71-C, 2-A, 3-B, 4-E, 5-D Each new lamp doubles the number of patterns: 2, 4, 8, 16, 32.
8a light switch, a coin on the table, a yes or no answer A light switch is on or off, a coin shows heads or tails, and yes or no are the only two answers. A dial and a box of paints have many settings.
94, 1, 3, 2, 5 They started with one lamp and added more until they had a pattern for every letter.
10Two lamps make four patterns, and three lamps make eight Two lamps make four patterns. It takes three lamps to make eight.
1116 Four lamps make 16 patterns, and five lamps make 32. 32 - 16 = 16 more patterns.
12Your own words: a grown-up reads it.
Mark each answer, count the right ones and write the score on the sheet.