10.5 Geometric sequences — Practise

1. Find the common multiplier and next term: $3,12,48,\ldots$.

Answer: Multiplier $4$; next term $192$.

2. Continue $96,48,24,\ldots$ by two terms.

Answer: $12,6$.

3. A geometric sequence starts at 2 and multiplies by 3. Find term 5

Answer: $162$.

4. Is $5,10,20,40$ geometric? Give the multiplier.

Answer: Yes; multiplier $2$.

5. Continue $2,-6,18,\ldots$ by two terms.

Answer: $-54,162$.

6. Sequence A starts at 3 and doubles. Sequence B starts at 2 and tr

Answer: B: $54$, compared with A's $24$.

7. A quantity starts at 80 and halves each hour. How much remains af

Answer: $5$.

8. A geometric sequence has first term 7 and common multiplier 2. Fi

Answer: $224$.