What is the sum of 2 by 3 and 4 by 9?
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NCERT Solutions Class 7 Mathematics Solutions for Exercise 4.1 in Chapter 4 - Simple EquationsQ4) Write equations for the following statements: (i) The sum of numbers x and 4 is 9. (ii) 2 subtracted from y is 8. (iii) Ten times a is 70. (iv) The number b divided by 5 gives 6. (v) Three-fourth of t is 15. (vi) Seven times m plus 7 gets you 77. (vii) One-fourth of a number x minus 4 gives 4. (viii) If you take away 6 from 6 times y, you get 60. (ix) If you add 3 to one-third of z, you get 30. Answer: Solution 4: (i) x+4=9 x=9-4 x= 5 (ii) y-2=8 y=8+2 y=10 (iii) a\times10\ =\ 70 (iv) \frac{b}{5}=\ 6\ b= 30 (v) \frac{3}{4}\times t\ =\ 15\ t\ =\ 15\times\frac{4}{3} t = 20 (vi) \frac{b}{5}=\ 6\ b\ =\ 6\ \times5\ b = 30 (vii) \left(\frac{1}{4}\times x\right)-\ 4\ =\ 4\ \frac{x}{4}-\ 4\ =\ 4\ \frac{x}{4}=4+4\ x\ =\ 8\times4 x= 32 (viii) 6y-6 = 60 6y = 60+6 6y = 66 y\ =\ \frac{60}{6} y = 11 (ix) \frac{z}{3}+\ 3\ =\ 30\ \frac{z}{3\ }=\ 33 z\ =\ 33\times3 z = 99
Video transcript hello everyone welcome to later homework session today we are going to solve a problem from the chapter linear equations so today's question is write equations for the following statements then we are given uh 9 statements and we need to convert them algebraic equations so let's start with the first one okay the sum of numbers x and 4 is 9. so whenever we see the number we see the word sum we know that the operation that needs to be performed is that of addition yes so we need to add x and 4 to get 9 so the algebraic equation that represents the statement the sum of numbers x and 4 is 9 is x plus 4 is equal to 9 with that we have answered the first sub question now let's go to the second sub question in the second sub question we are told 2 subtracted from y is 8 now clearly they have given us what operation we need to perform which is subtraction but also notice the word from so whenever you see the word from you know that the number that comes before from should come after minus yes so when we convert the second statement into an algebraic equation this will become y minus 2 it will not be minus y it will be y minus 2 because of the word from is 8 so this will be equal to 8. with that we have answered the second sub question now let's go to the third one the third question we are told 10 times a is 70. so whenever we see the word times we know that the operation here is multiplication yes so for the third problem we know that 10 times a is equal to 70 or 10 a is equal to 70. all right let's go to the fourth one the number b divided by 5 gives so here clearly they have given us what mathematical operation to perform we know that the mathematical operation will be performing as division so now b divided by gives us 6. so the mathematical equation for this statement will be b by 5 equal to 6 perfect now let us go to the fifth one the fifth one says 4 of t is so if i write it like that 3 will be written as 3 by 4 of t is 15. we know that whenever we see the operation off we replace it with a multiplication sign so this will be 3 by 4 multiplied by t is equal to 15 or t by 4 is equal to 15. so that will be the equation that represents this statement all right the next statement given to us is 7 times m plus 7 gets you 77 so the word times tells us that the mathematical operation is multiplication and the next word given is plus that tells us that there is addition okay so let's write this in the form of an equation times 7 multiplied by m plus 7 gives you 77 or 7 m plus plus 7 gives you 77 so that will be the equation that represents the sixth statement now let me clear out the board so that we have space to solve the test all right let's go to the seventh one in the seventh problem we are told one fourth of a number x minus four gives four so what are the mathematical operations in this statement the first operation is off the second one is minus so let us put this mathematically 4 of a number x minus 4 gives us 4 we know that whenever we see the operation off we replace it with the multiplication sign so 1 4 multiplied by x minus 4 is equal to 4 or x by 4 minus 4 is equal to 4 this is the equation that represents the th statement perfect let's go to the 8th one in the 8th problem we are told if you take away 6 from times y you get so let's look at the words that represent mathematical operation take away something means you subtract something again you see the word from so just like like we discussed in the second subsection here also the 6 will come after the minus sign the next word is times which means multiplication so let's write it in a mathematical form if you take away 6 from so something is going to come some term minus 6 so what is the term that comes before minus times y so 6 multiplied by y you will get 60. so this can be written as 6y minus 6 is equal to 60. all right okay now we have only one problem left i'm going to clear out some space so that we have enough room to do this the last subsection is if you add 3 to 1 3rd of z you get 30. so let's figure out what are the words that represent mathematical operations add off and you get so we know that when there is add we need to perform addition when there is off we use the mathematical operator of and you get is equal to equal to yes so let's solve the problem if you add 3 to third of z you get 30 so three plus one third multiplied by z is equal to 30 or 3 plus z by 3 is equal to 30 so that is a mathematical equation that represents the final statement that is given here all right i hope you found this video helpful and fun if you have any other questions or you know a different method of solving the same problem drop it in the comment section below hit subscribe to get regular updates about this channel and i'll see you in the next session until then take care bye Was This helpful?
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