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#1 2011-11-21 11:08:56
- princesscarla4
- New Scratcher
- Registered: 2011-11-09
- Posts: 8
Does anyone know this?
Hello, I am fairly new to this, and I am working on a project and I am trying to get a better understanding of everything, and had a few questions about scratch. Can anyone help me?
1) Once a variable contains a value, can that value be changed?
2) Can a variable contain a number, then later in the program, contain words, and if so could that be a bad thing?
3) If there are two loops, the outer executes 5 times, the inner executes 3 times. Inside the inner loop, there is a block of code that makes a sprite say "text". How many times will the sprite say, text'?
4) You have a program that has an if/else structure, and two variables, X and Y. The only time you want the alternative block(s) to execute is when both variables equal 10. What Boolean expression could you use for this situation?
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#3 2011-11-21 11:18:43
Re: Does anyone know this?
TRocket wrote:
1) yes it can be changed
2) yes
3)15 times
4)[blocks] << <( <{ X }> <=>10 )> <and> <( <{ Y }> <=>10 )> >>[/blocks]
Here's a clearer version of 4);
If (X = 10) and (Y = 10) then (ect..)
I'm back.
Maybe.
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#4 2011-11-21 11:27:58
- RedRocker227
- Scratcher
- Registered: 2011-10-26
- Posts: 1000+
Re: Does anyone know this?
1) Once a variable contains a value, can that value be changed?
Yes.
2) Can a variable contain a number, then later in the program, contain words, and if so could that be a bad thing?
Yes, and then no.
3) If there are two loops, the outer executes 5 times, the inner executes 3 times. Inside the inner loop, there is a block of code that makes a sprite say "text". How many times will the sprite say, text'?
15.
4) You have a program that has an if/else structure, and two variables, X and Y. The only time you want the alternative block(s) to execute is when both variables equal 10. What Boolean expression could you use for this situation?
X=10 and Y=10.
Hope I helped! 
Why
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#5 2011-11-21 13:55:00
- nightmarescratcher
- Scratcher
- Registered: 2011-10-10
- Posts: 1000+
Re: Does anyone know this?
RedRocker227 wrote:
1) Once a variable contains a value, can that value be changed?
Yes.
2) Can a variable contain a number, then later in the program, contain words, and if so could that be a bad thing?
Yes, and then no.
3) If there are two loops, the outer executes 5 times, the inner executes 3 times. Inside the inner loop, there is a block of code that makes a sprite say "text". How many times will the sprite say, text'?
15.
4) You have a program that has an if/else structure, and two variables, X and Y. The only time you want the alternative block(s) to execute is when both variables equal 10. What Boolean expression could you use for this situation?
X=10 and Y=10.
Hope I helped!
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#6 2011-11-21 16:26:30
- Ratty1967UK
- Scratcher
- Registered: 2007-05-16
- Posts: 88
Re: Does anyone know this?
Sounds like homework questions to me! hahaha 
also, the 4th question asks that the ALTERNATIVE block executes when both variables equal 10 - so your condition could be one of these two possibilities...
1. not (x = 10) or not (y = 10)
2. not ( x=10 and y=10 )
this interchangability between negated and/or conditions is called Demorgan's Law
Last edited by Ratty1967UK (2011-11-21 16:31:50)
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#7 2011-11-21 16:41:21
- RedRocker227
- Scratcher
- Registered: 2011-10-26
- Posts: 1000+
Re: Does anyone know this?
Ratty1967UK wrote:
Sounds like homework questions to me! hahaha
also, the 4th question asks that the ALTERNATIVE block executes when both variables equal 10 - so your condition could be one of these two possibilities...
1. not (x = 10) or not (y = 10)
2. not ( x=10 and y=10 )
this interchangability between negated and/or conditions is called Demorgan's Law
Oh yeah, I didn't realise that it said ALTERNATIVE blocks execute. That's what happens when you only skim the question though I guess 
Why
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#8 2011-11-22 09:22:40
- princesscarla4
- New Scratcher
- Registered: 2011-11-09
- Posts: 8
Re: Does anyone know this?
TRocket wrote:
1) yes it can be changed
2) yes
3)15 times
4)[blocks] << <( <{ X }> <=>10 )> <and> <( <{ Y }> <=>10 )> >>[/blocks]
-THANKS THIS HELPS A LOT-
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#9 2011-11-22 09:28:14
- princesscarla4
- New Scratcher
- Registered: 2011-11-09
- Posts: 8
Re: Does anyone know this?
DigiTechs wrote:
TRocket wrote:
1) yes it can be changed
2) yes
3)15 times
4)[blocks] << <( <{ X }> <=>10 )> <and> <( <{ Y }> <=>10 )> >>[/blocks]Here's a clearer version of 4);
If (X = 10) and (Y = 10) then (ect..)
-THANKS THIS HELPS A LOT-
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#10 2011-11-22 09:38:55
- princesscarla4
- New Scratcher
- Registered: 2011-11-09
- Posts: 8
Re: Does anyone know this?
RedRocker227 wrote:
1) Once a variable contains a value, can that value be changed?
Yes.
2) Can a variable contain a number, then later in the program, contain words, and if so could that be a bad thing?
Yes, and then no.
3) If there are two loops, the outer executes 5 times, the inner executes 3 times. Inside the inner loop, there is a block of code that makes a sprite say "text". How many times will the sprite say, text'?
15.
4) You have a program that has an if/else structure, and two variables, X and Y. The only time you want the alternative block(s) to execute is when both variables equal 10. What Boolean expression could you use for this situation?
X=10 and Y=10.
Hope I helped!
-THANKS THIS HELPS A LOT-
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#11 2011-11-22 09:42:14
- princesscarla4
- New Scratcher
- Registered: 2011-11-09
- Posts: 8
Re: Does anyone know this?
Ratty1967UK wrote:
Sounds like homework questions to me! hahaha
also, the 4th question asks that the ALTERNATIVE block executes when both variables equal 10 - so your condition could be one of these two possibilities...
1. not (x = 10) or not (y = 10)
2. not ( x=10 and y=10 )
this interchangability between negated and/or conditions is called Demorgan's Law
-THANKS THIS HELPS A LOT-
Offline
#12 2011-11-22 19:28:06
- Ratty1967UK
- Scratcher
- Registered: 2007-05-16
- Posts: 88
Re: Does anyone know this?
you're welcome - glad I could help
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