Question

120 is increased by d% then increased again by 25%

Answer 1

120 * (1 + d/100) * 1.25

Explanation:

Increase 120 by "d%": 120 * (1 + d/100)

Here, (1 + d/100) represents the factor by which we increase 120 based on the percentage "d".

Increase the above result by 25%: 120 * (1 + d/100) * 1.25

Here, we multiply the previous result by 1.25 to increase it by 25%.

So, the expression 120 * (1 + d/100) * 1.25 will give you the result after increasing 120 by "d%" and then increasing the result by 25%.

Answer 2

150 + 1.5d

Explanation:

120 is increased by d% :

120 + 120+d%

= 120(1 +d%)

`=120(1+(d)/(100) )\\\\=120((100+d)/(100))\\ \\= 12(100+d)/(10)\\ \\=6(100+d)/(5)`

then increased again by 25%

`=6(100+d)/(5)+6(100+d)/(5)*25\%\\\\=6(100+d)/(5)(1+ 25\%)\\\\=6(100+d)/(5)(1+(25)/(100))\\ \\=6(100+d)/(5)(1+(1)/(4)) \\\\= 6(100+d)/(5)((4+1)/(4) )\\\\ =6(100+d)/(5)((5)/(4) )\\\\=6(100+d)/(4)\\\\=3(100+d)/(2)\\\\=150 + 1.5d`