ACARA Digital Technologies Years 7–8 Word Scramble: Binary Number Representation (Modules 189–203)
Name:
Date:
Class:
🔤
Word scramble
Unscramble the letters and write each key term on the line.
1
SMOT TCAIISINGFN ITB
The leftmost bit of a binary number. It has the biggest place value, so it changes the number the most. The rightmost bit is the least significant bit.
2
210_1
A small 2 after a number shows it is binary (base 2). Say it digit by digit: one zero one. It means five in decimal, not one hundred and one.
3
61 8 4 2 1
The five binary place values. Use a 1 to count a place value and a 0 to skip it. Together they make any whole number from 0 to 31 as five bits, so 31 is 11111.
4
10001000
______ is the binary number 101 padded with leading zeros to fill 8 bits. Zeros added on the left do not change the value, so it is still 5.
5
TERAPDEE IVSINIOD YB 2
Divide a number by 2 again and again until the quotient is 0, noting each remainder. Read the remainders from last to first to get the binary number. Example: 13 is 1101.
6
VCNOTER KBAC
Check a decimal to binary answer by reading the binary back into decimal, adding the place values, and comparing with the starting number. If they match, it is right.
7
=E13NIDC(2B)
A spreadsheet function that converts a decimal whole number into binary text. ______ gives 1101. Add places to pad with zeros, e.g. =DEC2BIN(5,8) gives 00000101.
8
=1NCD21B(IE10)
BIN2DEC changes a binary number into its decimal value. ______ gives 13. Use it to check a hand conversion.
9
ANIRBY IITLAYRBLIE
Two states (on or off) are easy to tell apart even when signals are weak or noisy. Ten voltage levels would be easy to confuse, so binary makes errors less likely.
Answer Key
ACARA Digital Technologies Years 7–8 · Modules 189–203
1SMOT TCAIISINGFN ITB → most significant bit — The leftmost bit of a binary number. It has the biggest place value, so it changes the number the most. The rightmost bit is the least significant bit.
2210_1 → 101_2 — A small 2 after a number shows it is binary (base 2). Say it digit by digit: one zero one. It means five in decimal, not one hundred and one.
361 8 4 2 1 → 16 8 4 2 1 — The five binary place values. Use a 1 to count a place value and a 0 to skip it. Together they make any whole number from 0 to 31 as five bits, so 31 is 11111.
410001000 → 00000101 — 00000101 is the binary number 101 padded with leading zeros to fill 8 bits. Zeros added on the left do not change the value, so it is still 5.
5TERAPDEE IVSINIOD YB 2 → repeated division by 2 — Divide a number by 2 again and again until the quotient is 0, noting each remainder. Read the remainders from last to first to get the binary number. Example: 13 is 1101.
6VCNOTER KBAC → convert back — Check a decimal to binary answer by reading the binary back into decimal, adding the place values, and comparing with the starting number. If they match, it is right.
7=E13NIDC(2B) → =DEC2BIN(13) — A spreadsheet function that converts a decimal whole number into binary text. =DEC2BIN(13) gives 1101. Add places to pad with zeros, e.g. =DEC2BIN(5,8) gives 00000101.
8=1NCD21B(IE10) → =BIN2DEC(1101) — BIN2DEC changes a binary number into its decimal value. =BIN2DEC(1101) gives 13. Use it to check a hand conversion.
9ANIRBY IITLAYRBLIE → binary reliability — Two states (on or off) are easy to tell apart even when signals are weak or noisy. Ten voltage levels would be easy to confuse, so binary makes errors less likely.