2. Last week Robin did 30 sit-ups in 1minute. Today, she did 45 in1minute.her coach told her she improved 150%

Question

Is this true?
please explain

thank you very much

Answer 1

No, she improved by 45-30 or 15 situps.

15/30 = 50%

Answer 2

No, she improved by 50%. Because 50% of 30 is 15, and thus 45 is 50% more than 30. If she did 100% better, then she would have done 60 sit-ups. For 150%, this would have been 100% + 50% = 30 + 15 = 45 MORE sit-ups than 30, which is 75.

It's true that 45 is 150% of 30, but he said she IMPROVED BY this percentage, which again isn't true. I100% improvement for example means you've doubled your numbers. If she stayed at 30, that would be a 0% improvement, not 100%.

No wonder why this guy teaches phys ed!

Answer 3

No, this is not true.

Last week Robin did 30 sit-ups in 1 minute, this sets the base value of 30 as equal to 100%.

If Robin this week was able to do 45 sit-ups in the same time then she achieved 150% of her previous result.

The coaches statement that Robin "Improved 150%" is where the coach misrepresented what they were trying to say.

Mathematically an improvement is any amount above the original base value, therefore Robin improved by 15 sit-ups or 50% of her previous result.

Robin did however achieve a result of 150% of her previous effort. So she no doubt understood what her coach was trying to say and a 50% improvement in a week is still a good effort so I'm sure Robin wasn't too disappointed.

Answer 4

Its the wording that makes it incorrect. She did 150% of the situps that she did last week, but this equals an improvement of 50%. (i.e. 45 is 150% of 30, but 45 is 50% larger than 30)

Answer 5

This is actually a very interesting trick question. She did not improve by 150%, because that would mean that she would have to do 30 + 1.5 (30) situps in a minute, which is 75 situps per minute. Instead, she improved by 15 situps, which is15/30, or 50%.

Answer 6

no, 150% of 30 is 45 additional sit ups for a total of 75

Answer 7

yes.. this is true..because:
if 30 sit ups is 100%
then 15 sit ups[half of 30] is 50%
so 30sit ups = 100%
+ 15 sit ups = 50%
=45 sit ups = 150%

Answer 8

there two methods of expressing the improvement.
1st based on thepast performance.onthat basis.i.e. 15/30*100=50% improvement over the previous .It is 15/45*100=33.33%based on the present value of 45 situps

Answer 9

this is not true. Its not true because she actually improved 50%, because he second score was better than the first one by half of the first one....half is 50%

Answer 10

no, she just improved 50%. she did one half more than she had done the week before.