Distance

Grandfather had currant bushes planted in a row. The distance between neighboring bushes is 3m. By the first bush he has a well and a bucket (he will water two bushes). How many meters does he have to travel to water all 10 bushes? How many meters will the grandfather have to travel to water his bushes be reduced if he buys another bucket of the same type?

Correct answer:

l =  123 m
l₂ =  36 m

Step-by-step explanation:

$l=2\cdot 3+2\cdot (3+6)+2\cdot (3+6+6)+2\cdot (3+6+6+6)+1\cdot (3+6+6+6+6)=123\text{m}$

$$\begin{gathered} l_1=2\cdot (3+3+3)+2\cdot (9+12)+1\cdot (9+12+3+3)=87 \\ {l}_2=l-l_1=123-87=36\text{m} \end{gathered}$$

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