Easiest math problem ever

Algebra Level 2

If 1 + 2 + 3 + + 100 = x 1 + 2 + 3 + \cdots + 100 = x , find the value of 2 x 101 \dfrac{2x}{101} .

50 5050 non-rational number 100

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

2 solutions

1 + 2 + + 100 = 100 × 101 2 = x 1+2+\ldots +100=\dfrac{100\times101}{2}=x . Hence 2 x 101 = 2 × 101 × 100 2 × 101 = 100 \dfrac{2x}{101}=\dfrac{2 \times 101 \times 100}{2 \times 101}=\boxed{100} .

1 + 2 + 3 + . . . + 100 = x 1 + 2 + 3 + . . . + 100 = x

S = x = n 2 ( a 1 + a n ) = 100 2 ( 1 + 100 ) = 5050 S=x=\dfrac{n}{2}(a_1 + a_n)=\dfrac{100}{2}(1 + 100) = 5050

It follows that,

2 x 101 = 2 × 5050 101 = 100 \dfrac{2x}{101} = \dfrac{2 \times 5050}{101} = \color{#69047E}\boxed{100}

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...