You can
put this solution on YOUR website!Let x=weight of Pulse Jet
Then (x-20)=weight of Scramjet
And (x-20)+7=(x-13)=weight of Turbofan
Now we are told that:
x+(x-20)+(x-13)=1248 or
x+x-20+x-13=1248 simplify
3x-33=1248 add 33 to both sides
3x-33+33=1248+33 collect like terms
3x=1281 divide both sides by 3
x=427 kg--------------------weight of Pulse Jet
x-20=427-20=407 kg-------------------------weight of Scramjet
x-13=427-13=414 kg------------------------------weight of Turbofan
CK
427+407+414=1248
1248=1248
Hope this helps---ptaylor
