Time = 11/2 = 5 1/2
Road = 4 1/2 miles
Speed = 5 1/2 : 4 1/2 = 1 2/9 <------------answer
Simplified. Employ photomath for more detailed explanation.
To find the product of a reasonable estimate of two decimal numbers, round each decimals to the nearest whole number and then perform the multiplication.
For example:
3.2 x 5.7
Estimated answer
3.2 will be rounded down to 3 and 5.7 will be rounded up to 6
⇒ 3 x 6 = 18
Actual Answer
3.2 x 5.7
=18.24
Hello!
Since we are given that the speed of sound in the air travels about 343 meters per second, we can multiply 343 meters per second by 5, and then we convert the meters to kilometers.
343 · 5 = 1715 meters per 5 seconds.
1000 meters are equal to 1 kilometer. So, we can divide 1715 by 1000 to convert meters to kilometers.
1715 / 1000 = 1.715
Therefore, the speed of sound in air is about 1.715 kilometers per 5 seconds.
Answer: C. 6
Step-by-step explanation:
Given : Time taken by Machine R to do the job = 36 hours
Time taken by Machine S to do the job = 18 hours
Let x be the number of each type of machine to do the job.
Then , according to the question the required equation will be :-
Hence, the number of machines of type R were used =6