Answer:
343
Step-by-step explanation:
Big brain calculator work
28 + 35 + 42 + 49 + 56 + 63 + 70 = 343
There are two triangles, a big triangle and a small triangle that is inside the big triangle. Because the base of the triangles are parallel to each other( indicated by the arrow), and the small triangle is perfectly inside the bigger triangle, the sides of the triangles are proportional.
It is know that the base of the small triangle is 3.5, and the hypotenuse of the small triangle is 7cm. it is also known that the the hypotenuse of the big triangle is (7+8)=15 and the base of the big triangle is unknown.
Since the triangles are proportional,
to find the base of the big triangle
base(big)/hypotenuse(big)=base(small)/hypotenuse(small)
Plug in the numbers
x/15=3.5/7
x/15=1/2
x=15/2
x=7.5
The length of the base of the big triangle is 7.5cm
You should write numbers in as many ways as you possibly can to make new connections in your brain. Knowing how to write numbers in many different ways can help you solve complex problems more easily. Doing this can also reinforce the mathematical principles and logic you have memorised.
Writing one in many different ways:
1=1/1=2/2=3/3=4/4=(-1)/(-1)=(-2)/(-2)
=1.0=1.00=1.000=(1/2)+(1/2)=(1/3)+(1/3)+(1/3)
=(1/4)+(1/4)+(1/4)+(1/4)
Writing a half in many different ways:
1/2=(1/4)+(1/4)=(1/6)+(1/6)+(1/6)
=(1/8)+(1/8)+(1/8)+(1/8)=4*(1/8)
=2/4=3/6=4/8=5/10=0.5=0.50
etc...etc...
